因式分解(a+b)^2+4(a+b)c+4c^2

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（a+b）^2+4(a+b)c+4c^2
=(a+b)^2+2*2c*(a+b)+(2c)^2
=(a+b+2c)^2
(希望能帮纳悔到隐宏你灶茄册~)

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=(a+b)^2+2(a+b)*(2c)+(2c)^2
=(a+b+2c)^2

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