Question

The roots of x4 - 1 = 0 are​

Answer 1

Answer:

x=1,1,1,1

Step-by-step explanation:

hope it helps

Answer 2

Answer: 1 ,-1 , i

Step-by-step explanation:

we know that (a+b)*(a-b)=(a2 - b2)

x^4 - 1 =0 can be written as ( (x^2) +1 ) * ( (x^2) -1 )=0

let (x^2)+1=p and let (x^2) -1=q

now we need solution for p*q =0

either p=0 or q=0 for p*q=0

If p=0

(x^2) +1=0

(x^2)= -1

x=square root(-1)

x=i

If q=0

(x^2) -1=0

(x^2)=1

x=square root(1)

x= 1, -1