Find the LCD them make in into similar:

Question

-3y 4y^2
____ , _____

x-1 x^2-1

Answer 1

Find the LCD then make it into similar:

-3y/x-1 , 4y^2/x^2-1

i just rewrite it but i need your answer

Answer 2

You will need brackets around the denominator to obtain the proper order of operations

your second fraction factors to
4y^2/((x-1)(x+1))

so the LCD is (x-1)(x+1) or the original x^2 - 1

so you have

-3y(x+1)/(x^2 - 1) and 4y^2/(x^2 - 1)