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Questions (141)

A survey team is trying to estimate the height of a mountain above a level plain. From one point on the plain, they observe that
1. 1 answer
2. 474 views
A radio tower is located 450 feet from a building. From a window in the building, a person determines that the angle of
1. 2 answers
2. 1,512 views
a certain store sells two types of pen: one type for rs. 2 per pen and the other type for rs. 3 per pen. if a customer can spend
1. 1 answer
2. 668 views
after reducing the price by 20%, a calculators new price is $10. the original selling price of the calculator was?
1. 1 answer
2. 384 views
on a radio tower, a red light flashes every 6 seconds and a blue light flashes every 10 seconds. if both lights flash together
1. 1 answer
2. 621 views
two employees X and Y are paid a total of rs. 550 per week by their employer. if X is paid 120 percent of the amount paid to Y,
1. 1 answer
2. 871 views
the length of a rectangle is increased by 25%. by what percentage should the width be decreased so that the area of the
1. 1 answer
2. 717 views
find the capacity of an oil tank if an addition of 15 gallons raises the reading from 1/4 full to 5/8 full
1. 1 answer
2. 528 views
Nurse erika needs to prepare 12 liters of a 10% saline solution. The stockroom only has 7 % and 15% saline solutions. How much
1. 1 answer
2. 497 views
How many ounces of a 19% copper alloy metal must be added to 42% ounces of a 40% copper alloy metal to produce a metal which is
1. 0 answers
2. 536 views
Nurse erika needs to prepare 12 liters of a 10% saline solution. The stockroom only has 7 % and 15% saline solutions. How much
1. 1 answer
2. 798 views
Find the derivative of y=5^(1-4x)lny=(1-4x)ln5 Can I split it? lny=ln5-4xln5 1/y dy/dx = -[4ln5/(4xln5)^2]
1. 2 answers
2. 475 views
I need help to start this problem please,A company can sell 4500 pairs of sunglases monthly when the price is $5. When the price
1. 1 answer
2. 532 views
To construct a tincan, V=32pi m^3, The cost per square meter of the side is half of the top and bottom of can. What are the
1. 2 answers
2. 542 views
Find the horizontal asymptote off(x)=e^x - x lim x->infinity (e^x)-x= infinity when it's going towards infinity, shouldn't it
1. 0 answers
2. 571 views
Find the interval(s) where the function is increasing where and it is decreasing.f(x)=sin(x+(pi/2)) for 0≤x≤2pi so my
1. 3 answers
2. 1,144 views
Find the second derivative of the following function:y=log(base2)x/x² y'=[(x/ln2)-2xlog(base2)x]/x^4 the derivative of x/ln2 is
1. 2 answers
2. 582 views
I have trouble finding the second derivative, my answer is a little off from the answer key.f(x)=(log(base2)x)^5
1. 2 answers
2. 491 views
Find the derivative off(x)=x(1-4^x) f'(x)=(1-4^x)+ (-4^x)(ln-4)(-4)(x) ln can't be negative. Is the derivative correct?
1. 3 answers
2. 372 views
Find the linear approximation L(x) of the given function at a, and use it to approximate the function value at the given
1. 0 answers
2. 917 views
What's the domain of √((x-2)/(x^2+x-6))(2,infinity] ?
1. 2 answers
2. 357 views
lim x->1 (x^47-1)/(x^9-1)With what method do I factor them with? Pascal triangle?
1. 5 answers
2. 428 views
What is 4.38E+01 equal to?
1. 1 answer
2. 452 views
Consider the following buffer equilibrium:HF (high concentration) + H2O <--> H3O+ (low concentration) + F- ( high concentration)
1. 1 answer
2. 1,329 views
Find the area between y=cosx and y=sinx from 0 to 2pi.To find the zeros, I combined the equations cosx-sinx=0 What's next?
1. 3 answers
2. 728 views
Water will react most completely as an acid withA. SO3^-2 B. H2BO3- C. C6H5O- D. CH3COO- Why isn't the answer A, since H2O +
1. 4 answers
2. 956 views
What is the mass of NaOH required to prepare 100.0mL of NaOH(aq) thathas a pH = 13.62 ? A. 0.38g B. 0.42g C. 1.67g D.
1. 2 answers
2. 2,167 views
The S^2- ion is a relatively strong base with an equilibrium constant of 7.7x10^-1.What is the Ka value for HS- ? I got the
1. 4 answers
2. 928 views
Which solution will have the greatest electrical conductivity?A. 0.50MHCl B. 0.10MRbOH C. 0.50MK3PO4 D. 2.0MC6H12O6 I thought
1. 4 answers
2. 4,358 views
Differentiate:y=ln(x/(2x+3))^(1/2) y=(1/2)ln(x/(2x+3)) y'=0+(1/2)((2x+3-2x)/(2x+3)²) What's next after the quotient rule?
1. 2 answers
2. 405 views
Find the derivative.f(x)=(1+logᴈx)/x f'(x)=[1-ln3-logᴈx (ln3)]/(x²ln3) How do you simplify it further? Thanks.
1. 4 answers
2. 513 views
Write the net ionic equation for the hydrolysis reaction that occurs when Ba(CH3COO)2 is dissolved in water.CH3COO- + H2O <->
1. 3 answers
2. 1,142 views
Find the equation of the tangent line to the curve y=1+ xe^(2x)y'=(e^(2x))(2x+1) = slope What's the next step?
1. 2 answers
2. 439 views
A radar antenna is located on a ship that is 4km from a straight shore. It is rotating at 32rev/min. How fast does the radar
1. 2 answers
2. 2,424 views
Evaluate the following limit:lim x->(pi/2) [((pi/2)-(x))/cosx] May I please get a hint on how to start this question?
1. 1 answer
2. 1,055 views
Evaluate the following limit:lim x->0 xcscx =limx->0 x/sinx Does it equal one because the reciprocal is 1/1=1?
1. 1 answer
2. 620 views
Find dy/dx in the following:y=[x/√(1-x²)]- sin‾¹x y'={[(1-x²)^(1/2)-(-2x)(x)(1/2)(1-x²)^(-1/2)]/(1-x²)} -
1. 2 answers
2. 441 views
A vehicle moves along a straight path with a speed of 4m/s. A searchlight is located on the ground 20m from the path and is kept
1. 5 answers
2. 1,783 views
Is this correct?He saw construction workers building new buildings and he thought they worked hard for their dream and the
1. 3 answers
2. 516 views
Find the derivative ofy=cot³(1-2x)² y'=3[cot(1-2x)²]² (-csc²(1-2x)²)(2-4x)(-2) y'=(-6+24x)[cot(1-2x)²]²(-csc²(1-2x)²)
1. 2 answers
2. 804 views
Determine the concavity and find the points of inflection.y=2cosx + sin2x 0≤x≤2pi y'=-2sinx + 2cos2x y"=-2cosx-4sinx How do
1. 3 answers
2. 2,252 views
Find an equation of the tangent line to the given curve at the given pointy=(1/cosx)-2cosx at((pi/3),1) y'=0+2sinx slope = √3
1. 1 answer
2. 873 views
Find the derivative of y with respect to x:y=(1+cos²x)^6 y'=6(1+cos²x)^5 How do you derive inside the brackets? The answer
1. 2 answers
2. 616 views
Find the derivative of y with respect to x:y=3sin^4(2-x)^-1 y=[3sin(2-x)^-1]^4 y'=4[3sin(2-x)^-1]^3 (-3cos(2-x)^-1)(-1)
1. 0 answers
2. 577 views
Find the derivative of y with the respect to x:y=sin‾²(x³) y'=cos‾²(x³)(3x²) y'=3x²cos‾²(x³) How come my answer is
1. 1 answer
2. 424 views
What will be the [Cl-] when equal volumes of 0.10MNaCl and 0.20MAlCl3 are combined?A. 0.35M B. 0.15M C. 0.30M D. 0.70M
1. 2 answers
2. 1,176 views
In an experiment, a student mixes equal volumes of 0.0020M Pb 2+ ions with 0.0040M I- ions. The trial ion product is?PbI2 <-> Pb
1. 4 answers
2. 2,011 views
Consider the following equilibrium:CaCO3(s)<->Ca 2+(aq) + CO3 2-(aq) Which of the following reagents, when added to the
1. 2 answers
2. 3,179 views
If √2cos(x)-1 = (1+√3)/2 and √2cos(x)+1 = (1-√3)/2, find the value of cos4x.
1. 7 answers
2. 832 views
Find the value of tan2x, (pi/2)<x<pi, given secx=-5/4.So cosx=-4/5? I've no clue what to do next.
1. 2 answers
2. 627 views
Name three ways in which you can reduce the distortion due to diffraction of a wave passing through an aperture.-large aperture
1. 1 answer
2. 495 views
Solve identity,(1-sin2x)/cos2x = cos2x/(1+sin2x) I tried starting from the right side, RS: =(cos²x-sin²x)/(1+2sinxcosx)
1. 3 answers
2. 733 views
y=(√x)/((√x)+1)Find the concavity and point of inflection(s). y'=1/(√(x/2))(√x+1)²
1. 5 answers
2. 450 views
The wavelength of red light is about 7x10^-7m. The frequency of the red light reflected from a metal surface and the frequency
1. 2 answers
2. 2,010 views
y=x√(1-x²)Domain? y=x(1-x²)^(1/2) y=x/[(1-x²)^(-2)]? x≠±1 Symmetry? f(3)=192 f(-3)=-300 -f(-3)=300 no symmetry?
1. 3 answers
2. 439 views
Write an equation to show the dissolving of the following substance in water.(NH4)2SO4(s) NH42SO4 + H2O -> 2NH4 + SO4 + H^+ +
1. 4 answers
2. 1,265 views
Does the medium in which a wave travels move along with the wave itself.I think the answer is no, but why?
1. 4 answers
2. 968 views
Consider the following equilibrium:Mg(OH)2 (s) <--> Mg 2+ (aq) + 2OH-(aq) What happens to the amount of solid Mg(OH)2 when some
1. 2 answers
2. 2,175 views
Which of the following statements correctly describes the change which occurs when a liquid vaporizes at its boiling point at a
1. 2 answers
2. 1,380 views
What is the Keq of Cl2(aq) + 2HI2(g) -> I2(s) + 2HCl(s)Solid is not included in the Keq expression, so what would Keq be? Thanks
1. 5 answers
2. 727 views
A box is given a quick push so that it slides along a horizontal floor.a) What is its acceleration if the coefficient of kinetic
1. 1 answer
2. 478 views
A piece of wire 40cm long is cut into two pieces. One piece is bent into the shape of a square and the other is bent into the
1. 1 answer
2. 14,939 views
Describe the effect on the concentration of the bold substance by the following change: decrease the volumeThe equilibrium is:
1. 2 answers
2. 817 views
To start a sentence, "In spring"Is it "En printemps," or "Au printemps"? Merci.
1. 2 answers
2. 432 views
An artificial satellite placed into earth's orbit has a mass of 1250kg. It travels at an average distance of 222.5km above the
1. 3 answers
2. 1,458 views
Find the intervals of increase and decrease for the following function:y=x√((x-1)^4)
1. 3 answers
2. 487 views
Find the intervals of increase and decrease for the following functionh(x)=(x^3)(x-1)^4 h'(x)=[(3x^2)(x-1)^4]+(4x^3)(x-1)^3 How
1. 5 answers
2. 661 views
A water skier skis over the ramp, 5m vertical, 1m horizontal, at a speed of 12m/s. How fast is she risingas she leaves the ramp?
1. 2 answers
2. 1,714 views
I am desribing one of Pissarro's, (an Impressionist artist)painting. Are the vocabulary used correctly to dipict my meaning??Com
1. 1 answer
2. 532 views
A man 2m tall walks away from a lamppost whose light is 5m above the ground. If he walks at a speed of 1.5m/s, at what rate is
1. 7 answers
2. 8,647 views
How fast is the area of a square increasing when thh side is 3m in length and growing at a rate of 0.8m/min?I did Area=x^2
1. 7 answers
2. 2,800 views
Which of the following ions can be reduced from an aqueous solution?A)Ba2+ B)Al3+ C)Sn2+ D)Na+ Do I look for the higher volts?
1. 1 answer
2. 2,376 views
You have 5 metals A, B, C, D, E in 1.00M solutions of A^(3+), B^(3+), C^(3+), D^(3+), and E^(3+) respectively. When some of the
1. 2 answers
2. 477 views
Differentiate using the chain rule:y=(x+(x+x^(1/2))^(1/2))^(1/2) y'=(1/2)(x+(x+x^(1/2))^(1/2))^-(1/2) what are the next steps?
1. 0 answers
2. 460 views
At what points on the curve y=(x^2)/(2x+5) is the tangent line horizontal?y'=[(2x)(2x+5)-(2)(x^2)]/(2x+5)^2 =[2x^2+10x]/(2x+5)^2
1. 1 answer
2. 781 views
Differentiate the following function:y= [x+1]/√x I tried y=[x+1]/x^(1/2) y' =1/2√x y'=2√x Thanks in advance.
1. 6 answers
2. 414 views
FInd f'(a) for the function, f(x)=(1+2x)/(1+x)lim h->0 ][(1+2(a+h))/(1+a+h)]-[(1+2a)/(1+a)]]/h I got rid of the denominator lim
1. 3 answers
2. 627 views
If a ball is thrown into the air with a velocity of 30m/s, its height in metres after t seconds is given by y=30t-4.9t^2Fing the
1. 1 answer
2. 2,483 views
lim x->3 ((x^-2)-(3^-2))/(x-3)
1. 2 answers
2. 451 views
lim h->0 (((1/(1+h))-1)/hI don't understand how the answer is -1 shouldn't it be 0?
1. 2 answers
2. 398 views
Determine the coefficient of the 3rd term in the expansion of (x+2y)^7.I tried using the formula,nCk (a^(n-k)) ((b)^k), but it
1. 1 answer
2. 525 views
Simplify: 9log(base27)x - 4log(base9)xusing no calculators. Thanks in advance.
1. 1 answer
2. 419 views
For what values of x(x≠0) will the following infinite geometric series have a finate sum?x+3x²+9x³+... 3x²/x what are the
1. 2 answers
2. 775 views
The point (5,-6) is on the terminal arm of the standard position angleӨ. Determine the smallest positive measure of Ө in
1. 1 answer
2. 1,668 views
If the point (6, -12) is on the graph of y=f(x), which point must be on the graph of y=f((-1/3x)+6)?so far, I have
1. 0 answers
2. 376 views
How many 4-digit whole numbers are there? For example, 1220 is acceptable but 0678 is not.How do you do permutation and
1. 1 answer
2. 368 views
He rarely brushes his hair:Il se brosse les cheveux rarement I remember the rule that adverbs go after the verb, but I think it
1. 1 answer
2. 447 views
60% of the hockey players are from Eastern Canada and 40% are from Western Canada. 18% of the Eastern players and 12% of the
1. 4 answers
2. 556 views
Prove the identity:1-cos2x/sin2x = 1+tanx/1+cotx I simplified the RS to tanx. LS:(1-2cos²x+1)/2sinxcosx (2+2cos²x)/2sinxcosx
1. 2 answers
2. 1,307 views
Proving identity(sinx+tanx)/(cosx+1)=tanx RS: (sinx+(sinx/cosx))/(cosx+1) ((sinxcosx/cosx)+(sinx/cosx))x 1/(cosx+1)
1. 1 answer
2. 610 views
state the values of x for which the following identiy is truelog(x+2) + log(x+3) = log(x^2+5x+6) a) x> -2 b) x> -3 Why is the
1. 2 answers
2. 494 views
How would SiO4 Lewis structure look like?Each oxygen has 1 unfilled electron, so would there be 2 double bonds? Thanks in
1. 7 answers
2. 4,723 views
Two cards are drawn without relplacement from a shuffled deck of 52 cards. Determine the probability of each event.a)The first
1. 3 answers
2. 954 views
Two cards are drawn wtihout replacement from a shuffled deck of 52 cards. What is the probability that the second card is each
1. 2 answers
2. 525 views
Which of the following elements would have the largest third ionization energy: K, Ca, Ga?What is third? Thanks in advance.
1. 7 answers
2. 2,225 views
The place that you're going to go to is the park.L'endroit que vous irez est le parc. A French corrector indicated that I need a
1. 3 answers
2. 385 views
Why do you think that the ionization energy tends to decrease within a family of the periodic table?Since ionization energy
1. 2 answers
2. 551 views
Write the core notation ofSr 2+ is it [Ar] 3d10 4s2 4p6 or [Ar]4s2 3d10 4p4 5s2 since you subtract from p before s before d
1. 3 answers
2. 1,137 views
What is the third number in the 156th row of Pascal's triangle?I know that it is 154 x ___ how do I find out the number? thanks
1. 4 answers
2. 710 views