Question

What is the relative maximum and minimum of the function?
f(x) = 2x2 + 28x - 8
A. Minimum Value: -106 Range y > -106
B. Minimum Value: -106 Range y > -7
C. Minimum Value: 7
Range y > 7
D. Minimum Value: -7 Range y > -7
i already know its not D.

Answer 1

@turnupreal

Answer 2

Well, since this is a parabola going upwards you just need to equal the dervative to zero and solve for x.
dfdx=4x+28=0→x=−284=−7
Then solve for f.
f=114
Thats the minimum. The maximum is infinity because as x goes to either side of minus seven, f gets bigger and bigger.

Answer 3

did that help

Answer 4

that would make the answer...?

Answer 5

what is the dervative and how do i equal it to zero

Answer 6

@IMxLORDxGOTEN

Answer 7

im back

Answer 8

can you help

Answer 9

yush

Answer 10

okay thanks

Answer 11

hmmmmmmmmmmmmmmm