Question

[Emi]

Tìm a

(a+1)x(a+2)x(a+3)- a x (a+1)x (a+2)

Answer 1

[okazaki * Nightcore - Nỗi đau từ....]

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https://olm.vn/hoi-dap/detail/9212510579.html

hok tốt

Answer 2

[Trần Đại Nghĩa]

\(\left(a+1\right)\times\left(a+2\right)\times\left(a+3\right)-a\times\left(a+1\right)\times\left(a+2\right)\)

\(=\left(a+3\right)\times\left[\left(a+1\right)\times\left(a+2\right)\right]-a\left[\left(a+1\right)\times\left(a+2\right)\right]\)

\(=\left[\left(a+3\right)-a\right]\times\left[\left(a+1\right)\times\left(a+2\right)\right]\)

\(=\left[3+\left(a-a\right)\right]\times\left[\left(a+1\right)\times\left(a+2\right)\right]\)

\(=3\times\left[\left(a+1\right)\times\left(a+2\right)\right]\)

\(=\left[3\times\left(a+2\right)\right]\times\left(a+1\right)\)

\(=\left(3\times a+3\times2\right)\times\left(a+1\right)\)

\(=\left(3\times a+6\right)\times\left(a+1\right)\)