SOLUTION: Help please I need to know how to factor this problem x^5-4x^3-8x^2+32

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Question 55046: Help please I need to know how to factor this problem x^5-4x^3-8x^2+32
Found 2 solutions by anjulasahay, funmath:
Answer by anjulasahay(30) About Me  (Show Source):
You can put this solution on YOUR website!
Help please I need to know how to factor this problem x^5-4x^3-8x^2+32
ans:
x^5-4x^3-8x^2+32=x^3(x^2-4)-8(x^2-4)=(x^3-8)(x^2-4)
=(x-2)(x^2+2x+4)(x-2)(x+2) [ since a^3-b^3=(a-b)(a^2+ab+b^2) and
(a^2-b^2)=(a+b)(a-b)]

Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E5-4x%5E3-8x%5E2%2B32
First factor by grouping:
%28x%5E5-4x%5E3%29%2B%28-8x%5E2%2B32%29
x%5E3%28x%5E2-4%29-8%28x%5E2-4%29
%28x%5E3-8%29%28x%5E2-4%29
The 1st set of parenthesis is the difference of cubes x^3=(x)^3 and 8=(2)^3 the formula for that is highlight%28a%5E3-b%5E3=%28a-b%29%28a%5E2%2Bab%2Bb%5E2%29%29 (a=x and b=2) and the second is the difference of squares x^2=(x)^2 and 4=(2)^2 the formula for that is: highlight%28a%5E2-b%5E2=%28a%2Bb%29%28a-b%29%29 (a=x and b=2)
%28x-2%29%28x%5E2%2B%28x%29%282%29%2B%282%29%5E2%29%28x%2B2%29%28x-2%29
%28x-2%29%28x%5E2%2B2x%2B4%29%28x%2B2%29%28x-2%29
%28x-2%29%28x-2%29%28x%2B2%29%28x%5E2%2B2x%2B4%29
%28x-2%29%5E2%28x%2B2%29%28x%5E2%2B2x%2B4%29
Happy Calculating!!!