# i need help with these equations

**Question description**

1.Suppose

y = f(x)

is a curve that always lies above the *x*-axis and never has a horizontal tangent, where *f* is differentiable everywhere. For what value of *y* is the rate of change of

y^{4}

with respect to *x* thirty-two times the rate of change of *y* with respect to *x*?

2.Find the 80th derivative of

y = cos 3x.

3.If

F(x) = f(xf(xf(x))),

where

f(1) = 2, f(2) = 3, f '(1) = 3, f '(2) = 4,

and

f '(3) = 5,

find

F '(1).

F '(1) = 1

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