Is y = 1/2x - 7 and y = x² + 1 a function?​

Divide both sides by 1-y. Divide both sides by 1−y. Dividing by 1-y undoes the multiplication by 1-y. Dividing by 1− y undoes the multiplication by 1−y. Subtract xy from both sides. Subtract xy from both sides.

If f(x) is an anti-derivative of g(x), then g(x) is the derivative of f(x). Similarly, if g(x) is the anti-derivative of h(x), then h(x) must be the derivative of g(x). Therefore, h(x) must be the second derivative of f(x); this is the same as choice A. 

I hope this helps.