Perform the operation Simplify your answer completely x 3x2

Perform the operation. (Simplify your answer completely.) (x + 3)(x^2 + 3x + 5) Perform the operation. (Simplify your answer completely.) (8n + 1)(8n - 1) Perform the operation. (Simplify your answer completely.) (w^2 + w - 7)(w^2 - w + 4) Perform the operation. (Simplify your answer completely.) (4t - 1)^2 Perform the operation. (Simplify your answer completely.) 4y (y + 9)

Solution

21)

(x+3)(x²+3x+5)

=((x+3)(x²))+((x+3)(3x))+((x+3)(5))

=(x³+3x²)+(3x²+9x)+(5x+15)

=x³+6x²+14x+15

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22)

(8n+1)(8n-1)

=(8n(8n-1)) +(1(8n-1))

=((8n*8n)-(8n*1)) +((1*8n)-(1*1))

=(64n²-8n) +(8n-1)

=64n²-1

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23)

(w²+w-7)(w²-w+4)

=((w²+w-7)(w²))+((w²+w-7)(-w))+((w²+w-7)(4))

=(w⁴+w³-7w²)+(-w³-w²+7w)+(4w²+4w-28)

=w⁴-4w²+11w-28

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24)

(4t-1)²

=(4t-1)(4t-1)

=(4t(4t-1))+(-1(4t-1))

=(16t²-4t)+(-4t+1)

=16t²-8t+1

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25)

4y(y+9)

=(4y *y) +(4y*9)

=4y² +36y