ROVIKULY 2.07 : (x + 5)^3 = ? (problem with solution)

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Transcript:
Please calculate:
x plus 5, all cubed.

FORMULA:
a plus b, all cubed,
equals
a cubed
plus 3 a squared b
plus 3 a b squared
plus b cubed.

SOLUTION:
x plus 5, all cubed,
equals
x cubed
plus 3 times x squared times 5
plus 3 times x times 5 squared
plus 5 cubed.

Which equals:
x cubed
plus 3 times 5 times x squared
plus 3 times 25 times x
plus 125.

Which equals:
x cubed
plus 15 x squared
plus 75x
plus 125.

ANSWER:
x plus 5, all cubed
equals
x cubed
plus 15 x squared
plus 75x
plus 125.

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