i need help por favor please teach me step by step?

Question

If f(x)=5x^2-11x-1, find f'(x)____

Find f'(5)_____

Answer 1

power rule

f ' (x) = 10 x -11

f ' (5) = 10 * 5-11=39

Answer 2

Remember that:

f'(x^n) = n(x)^(n-1)

So, f'(x^2) = 2x and f'(x) = 1.

Also, the derivative of a constant is 0.

So, f'(x) = 5f'(x^2) - 11f'(x) - f'(1) = 10x - 11

And, f'(5) = 10*5 - 11 = 39

Answer 3

once you've done the first part the second is simple.

use the power rules on the first problem to find f'(x): if f(x)=x^y then f'(x) = y*(x^(y-1)), and recall that the derivative of a constant is just zero.

f'(x) = 5*2*[x^(2-1)]-11*1*[x^(1-1)]+0

f'(x)=10x-11

now, to find f'(5), just plug in 5 for x

f'(x)=10x-11
f'(5)=10(5)-11
f'(5)=39

Answer 4

1.) take the power, and multiply the coeficcient by it. then reduce the power on the x factor by 1.

If there is no x, delete that term.

2*5x -11 -0
10x-11=f'(x)

2.) put 5 instead of x. solve.

Answer 5

39

Answer 6

Take the derivative of each term and get
f'(x) = 10x -11
Then plug in 5 for x to get
f'(5) = 10*5 - 11 = 39

Doug

Answer 7

f(x) = 5x^2-11x-1

f'(x) = 10x-11 (basic derivative)

f'(5) = 10(5)-11

f'(5) = 39