因式分解难题:a^3b^2+ab^2+30b^2要求:拆项或添项分组分解法的因式分解

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因式分解难题:a^3b^2+ab^2+30b^2要求:拆项或添项分组分解法的因式分解
因式分解难题:a^3b^2+ab^2+30b^2
要求:拆项或添项分组分解法的因式分解

因式分解难题:a^3b^2+ab^2+30b^2要求:拆项或添项分组分解法的因式分解
a³b²+ab²+30b²
=b²(a³+a+30)
=b²(a³-9a+10a+30)
=b²[a(a+3)(a-3)+10(a+3)]
=b²[(a+3)(a²-3a+10)]
=b²(a+3)(a²-3a+10)

a^3b^2+ab^2+30b^2
=b^2(a^3+a+30)
=b^2(a+3)(a^2- 3a +10)
--------------------------------------------
let
f(a) = a^3+a+30
f(-3) = 0
a+3 is a factor
f(a) = (a+3)(a^2+k...

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a^3b^2+ab^2+30b^2
=b^2(a^3+a+30)
=b^2(a+3)(a^2- 3a +10)
--------------------------------------------
let
f(a) = a^3+a+30
f(-3) = 0
a+3 is a factor
f(a) = (a+3)(a^2+k1a+k2)
compare coef of constant
3k2 = 30
k2 = 10
compare coef of a
3k1+k2=1
k1= -3
f(a) = (a+3)(a^2-3a+10)
a^3b^2+ab^2+30b^2 =b^2(a+3)(a^2- 3a +10)

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