Question

Find the equation of the line tangent to the graph of f at (3, 140), where f is given by f(x) = 8x^3 − 9x^2 + 5.

Answer 1

just differentiate the cubic equation to get f'(x)

Answer 2

now f'(3) will give you slope of tangent

Answer 3

24x^2-18x

Answer 4

now you have slope of tangent and a point in the tangent , use slope point form to write equation of tangent

Answer 5

f'(3)?

Answer 6

yep substite x=3 in the differential

Answer 7

so slope is 162

Answer 8

so now the mx+b?

Answer 9

slope point form

y-y1=m(x-x1)

Answer 10

gt it?

Answer 11

yeah

Answer 12

:)

Answer 13

y-140=162(x-3)?

Answer 14

right

Answer 15

yep

Answer 16

thanks

Answer 17

welcomes