例1y=2x3-5x2+3x-7,求y 解y=(2x3-5x2+3x-7 =(2x3)-(5x2)y+(3x)-(7) 2(x3)y-5(x2)+3(x) =23x2-52x+3 =6x2-10x+3
结束 y=(2 x 3 − 5 x 2 + 3 x −7) =(2 x 3 )− ( 5 x 2 )+(3 x )−(7) = 2(x 3 )−5(x 2 )+3(x ) = 2 3 x 2 − 5 2x + 3 = 6 x 2 −10 x + 3 例 1 y = 2 x 3 − 5 x 2 + 3 x − 7 求y 解
