Answer:
x=√2, x=-√2, x= 3 and x=-3
Step-by-step explanation:
We need to solve the equation x^4 - 11x^2+18=0
We can replace x^4 = u^2 and x^2 = u
So, the equation will become
u^2 -11u+18 = 0
Factorizing the above equation:
u^2 -9u-2u+18 =0
u(u-9)-2(u-9)=0
(u-2)(u-9)=0
u=2, u=9
As, u = x^2, Putting back the value:
x^2 =2 , x^2 =9
taking square roots:
√x^2 =√2 ,√x^2=√9
x=±√2 , x = ±3
so, x=√2, x=-√2, x= 3 and x=-3
Answer:
$2.50
Step-by-step explanation:
Answer:
39%
Step-by-step explanation:
83-last price
83 last price
100 x ?
100 * last price = 83 . x
x= 39
Answer:
x= 3 inch should be turned up on each side
Step-by-step explanation:
Let the height of trough be x.
Width of trough be 12 - 2x.
and length of trough = 120 inch
Volume of trough, V = L×W×H = 120 × (12-2x) × x = 120x(12 - 2x)
For maximum volume, we find V' = 0
i.e 1440 -480x = 0
or x = 
or x= 3
Hence x= 3 inch should be turned up on each side
