已知A=x的平方-2x+1,B=7x-8,且3A-C=2B,求C

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已知A=x的平方-2x+1,B=7x-8,且3A-C=2B,求C
已知A=x的平方-2x+1,B=7x-8,且3A-C=2B,求C

已知A=x的平方-2x+1,B=7x-8,且3A-C=2B,求C
3A-C=2B
C=3A-2B
=3(x²-2x+1)-2(7x-8)
=3x²-6x+3-14x+16
=3x²-20x+19
绝对正确,请放心采纳!

3*(x^2-2x+1)-C=2*(7x-8)
C=3x^2-6x+3-14x+16=3x^2-20x+19

c=3A-2B
=3(x^2-2x+1)-(7x-8)
3x^2-6x+3-7x+8
=3x^2-13x+11

A=x²-2x+1,B=7x-8,且3A-C=2B,求C=?A=x²-2x+1=(x-1)²①,B=7x-8=7x-7-1=7(x-1)-1②,将3A-C=2B转换为
C=3A-2B=3(x-1)²-2*[7(x-1)-1]=3(x-1)²-14(x-1)+2=3x²-20x+19