Question

1)Find cos theta if sin theta=3/5 and 90 degrees<theta<180 degrees.
A)4/5
B)-4/5
C)square root of 34/5
D)-square root of 34/5
I chose A

2)Simplify:1-csc^2theta/cot^2theta
A)-1
B)1
C)tan^2theta
D)1/sin^4theta
I chose C

3)Simplify:-5(cot^2theta-csc^2theta)
A)5
B)-5
C)-5csc^2 theta
D)5csc^2 theta
I chose B

4)Which expression is not equivalent to 1?
A)sin^2theta+cot^2thetasin^2theta
B)sin^2theta/1-costheta -1
C)sec^2theta+tan^2theta
D)cot^2thetasin^2theta/cos^2theta
I don't know

5)Which expression is equivalent to tan theta-sec theta/sin theta?
A)-cot theta
B)cot theta
C)tan theta-cot theta
D)tan theta-sec^2theta
I don't know

Answer 1

Are you studying for a trig test?

Just curious!

Where is your effort?

Why do you not try to solve each question and show your work?

Then we can help you better.

I would like to know if you are preparing for a math state test.

Answer 2

I have been showing my work in my book but not for these questions b/c I have no clue as to how to solve them its just I need them to be checked and its just too time consuming to post the work on the computer. I really appreciate everyone's help.

Answer 3

Thank you for being honest.

I don't mind helping you when there is time. However, I will only solve one or two questions and allow others to do the rest.

Answer 4

Thank you

Answer 5

I am willing to do one just to show you how. Express all functions as sin and cos, for example tan = sin/cos and then remember that sin^2 + cos^2 = 1
4)Which expression is not equivalent to 1?
A)sin^2theta+cot^2thetasin^2theta
B)sin^2theta/1-costheta -1
C)sec^2theta+tan^2theta
D)cot^2thetasin^2theta/cos^2theta
I don't know

A)--> sin^2 T ( 1 + cos^2 T/sin^2T)
= sin^2T+ cos^2 T = 1

B) --> sin^2 T/(1-cos T) - 1
= sin^2 T (1+cos T)/(1-cos^2T) - 1
= 1 + cos T - 1
this is not 1

C) --> 1/cos^2 T + + sin^2/cos^2 T
= (1+sin^2 T)/cos^2T
that is not 1 either, but I bet you have a typo in the original sign

D) --> cot^2thetasin^2theta/cos^2theta
= (cos^2 T sin^2T)/(sin^2 T cos^2 T)
= 1