Question

I'm studying for a test so I want to make sure I'm doing these problems right.

Numerator (-5a exponent -2)
Denominator b3
All to the -1 exponent

For a= -4. And b=2

My answer I get is 1/10 is the right ?



-16 with -1/2 exponent
Would the answer be -4?

2-3 square root of 14
Would the answer be -1 square root 14 ?

5/square root 20 -2 square root 45
I get 2 as my answer is this right ?


3/y+2 + 2/y = 5y-4/y2-4
Got my LCD as y(y-2)(y+2)
I know you distribute LCD but idk how to solve ! Help please!!

Answer 1

It would be nice if you used standard notation for stuff.

-5a^-2/b^3 = (-5)(1/16)/8 = -5/128
(-5a)^-2/b^3 = (20)^-2/8 = 1/3200
How did you arrive at 1/10?

-16^(-1/2) = -1/4
Negative exponents mean reciprocals

(2-3)√14 is indeed -√14

5/√20 - 2/√45 = 5/(2√5) - 2/(3√5)
= 1/√5 (5/2 - 2/3)
11/(6√5) or 11/30 √5

3/(y+2) + 2/y = (5y-4)/(y^2-4)
clear denominators and you get
3y(y-2) + 2(y^2-4) = (5y-4)y
3y^2 - 6y + 2y^2 - 8 = 5y^2 - 4y
-2y - 8 = 0
y = -4