Question

find max of function. f(x) = -x^4+2x+3.
let t=x^2

Answer 1

really?

Answer 2

really

Answer 3

that does not help your cause at all.

Answer 4

give me a medal

Answer 5

maybe it would if it was
\[f(x)=-x^4+2x^2+3\]

Answer 6

are you sure it is just
\[f(x)=-x^4+2x+3\]? because if you replace x^2 by t you get
\[-t^2+2\sqrt{t}+3\] a big mess

Answer 7

it says hint: let t=x^2

Answer 8

can you give me a medal

Answer 9

nvm i got it using calculator

Answer 10

-2t-1/radt=0
2t=1/radt
t^3/2=1/2
t=(1/2)^2/3
x=((1/2)^2/3)^2 ARE YOU CRITICAL POINTS AND NOW TAKE 2ND DER to find if its a max or min

Answer 11

x=((1/2)^2/3)^1/2

Answer 12

@bnut056 apparently this is not a calc course

Answer 13

ha opps then i dont know what hes asking