- #1
AllanW
- 18
- 0
Homework Statement
find the inflection points of x^2-4√x
Homework Equations
The Attempt at a Solution
Okay, I started with finding the derivatives;
f'(x)=2x-2/√x
f''(x)=2+1/√x^3
and made the second derivative =0
(2+1/√x^3=0)(√x^3)
2√x^3+1=0
(√x^3=-1/2)^2
x^3=1/4
x=cube root(1/4)
x=0.63
But when I enter '0.63' into the second derivative i get '4' (2+1/(√0.63^3)=4) Should i not get 0? Does this mean there are no inflection points?