Question

find all zeroes of x^4 - 2x^3 -8x^2 +10x + 15​

Answer 1

Answer:

x=1, -3, 5, -5

Step-by-step explanation:

Here, the given polynomial equation

p(x) =x⁴-2x³-8x²+10x+15

Let, p(x) =0

x⁴-2x³-8x²+10x+15=0

=>x⁴-2x³-(3x²+5x²)+10x+15=0

=>x⁴-2x³-3x²-5x²+10x+15=0

=>x²(x²-2x-3)-5(x²-2x-3)=0

=>(x²--5)(x²-2x-3)=0

=>x²-5=0 or (x²-2x-3)=0

=>x²=5 or (x²+3x-x-3)=0

=>x=±5 or [x(x+3)-1(x+3)]=0

=>x=±5 or (x+3)(x-1)=0

=>x=±5 or x=-3 or x=1