Question 367353
Multiply:
(x^2+x+4)(x-4)
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= (x^2+x+4)x - (x^2+x+4)4
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= x^3+x^2+4x -4x^2-4x-16
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= x^3-3x^2+16
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Add:
(8x^2-xy+y^2)+(-x^2-4xy+6y^2
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= 7x^2-5xy+7y^2
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Factor By Grouping:
4x^3-28x^2-3x+21
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= 4x^2(x-7)-3(x-7)
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= (x-7)(4x^2-3)
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Factor:
3c^7-192c^4
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= 3c^4[c^3-64]
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= 3c^4(c-8)(c^2+8c+16)
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Cheers,
Stan H.