Question

Which of the following is an equation of the line tangent to the graph of f(x)=x^4/4-x^3 at the point where f'(x)=1?

a) y=x+3.5954
b) y=x-9.803
c) y=x-3.056
d) y=x-1
e) y=3x-1

Answer 1

@whpalmer4 @.Sam. @satellite73 @mathmale @thomaster

Answer 2

@SolomonZelman @Hero @amistre64

Answer 3

@Luigi0210 @robtobey

Answer 4

@goformit100 @Compassionate @agent0smith

Answer 5

Please help me, it's urgent.

Answer 6

@Destinymasha @jim_thompson5910

Answer 7

You'd have to start by differentiating, and setting the slope equal to 1, since f'(x)=1, and solving for x.

Then plug that x into the f(x)=x^4/4-x^3

Answer 8

A quick pencil sketch of the curve might also give you your answer. We can eliminate e) off the bat because the slope isn't 1, which it must be to be the tangent to a function whose first derivate = 1 at that point.

Answer 9

we can easily find the other zero of the function is at x = 4:



that means 0 < x < 4

3 of the 4 remaining answer choices will be positive near the right end of the interval, so they won't work.