Answer:
2 solutions
Step-by-step explanation:
x^4-6x^2-7=0
Replace x^2 by y
(x^2)^2-6x^2-7=0
y^2-6y-7=0
D=b^2-4ac= (-6)^2-4*1*(-7)= 36+28=64
sqrtD=8
y1=(-b-sqrtD)/2a=-2/2=-1
y2= (-b+sqrtD)/2a=14/2=7
x^2=-1(n0 roots) x^2=7 x=sqrt7 or x=-sqrt7
2 roots
I think it would be $14 per book
Step-by-step explanation:
hi the steps are in the picture attached by me
Answer:
Because 4 is a perfect square
Step-by-step explanation:
When simplifying a radical, you have to look for perfect squares. 4 is a perfect square but x is not. Variables are only perfect squares if they have even numbered exponents so the x has to stay in the radical.
