已知a+b=4,求-2(a+b)²+3a-17+3b的值
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已知a+b=4,求-2(a+b)²+3a-17+3b的值
已知a+b=4,求-2(a+b)²+3a-17+3b的值
已知a+b=4,求-2(a+b)²+3a-17+3b的值
-2(a+b)²+3a-17+3b
=-2(a+b)²+3(a+b)-17
a+b=4
-2(a+b)²+3(a+b)-17
=-2x16+3x4-17
=-32+12-17
=-37
-2(a+b)²+3a-17+3b
=-2(a+b)²+3(a+b)+17
=-2*4²+3*4+17
=-16+12+17
=13
-2(a+b)²+3a-17+3b=-2(a+b)²+3(a+b)-17=-2*4^2+3*4-17=-37