Question

f(x)=x(x-4)(x+4) and g(x)=(x²-36)(x²-4) how do I find the values for f(x) x g(x) > 0 ?

Answer 1

define where f or g equals zero, then run some test points inbetween the intervlas

Answer 2

the intervals that are + are by default ... greater than zero

Answer 3

I have the zeros of both

Answer 4

then lets test them out ....

Answer 5

fg = x(x-4)(x+4)(x²-36)(x²-4)

-6 -4 -2 0 2 4 6

let x = +- 1, +- 3, +- 5 and +- 10

and see how they interact

Answer 6

for x=-1

x (x-4) (x+4) (x²-36) (x²-4)
- - + - -

-- = +
-- = +
+ = +

therefore the overall sign is + between -2 and 0

Answer 7

oh, I see..

Answer 8

thank you

Answer 9

youre welcome