Question

if f(x)=8-2x^2,how many integers satisfy the condition that f(x) is positive?

Answer 1

8-2x^2 >0
2(4-x^2)>0
4-x^2 >2
x^2< 4
-2<x<2

Answer 2

they are 3..
-1,0,1

Answer 3

thanks.:)

Answer 4

my pleasure XD

Answer 5

let f(x) = 0 then 8 - 2x^2 = 0 or 8 = 2x^2 then 4 = x^2

then \[x = \pm 2\]

or
\[-2\le x \le 2\]