计算(1)(4a-b²)*(-2b)(2)2*x²(x-2分之1)(3)5ab*(2a-b+0.2)(4)(2a²-3分之2a-9分之4(1)-8ab+2b³(2)2x³-x³(3)10a²b-5ab²+ab(4)-18a³+6a²+4a(4)(2a²-3分之2a-9分之4 )*(-9a)

问题描述:

计算(1)(4a-b²)*(-2b)(2)2*x²(x-2分之1)(3)5ab*(2a-b+0.2)(4)(2a²-3分之2a-9分之4
(1)-8ab+2b³(2)2x³-x³(3)10a²b-5ab²+ab(4)-18a³+6a²+4a
(4)(2a²-3分之2a-9分之4 )*(-9a)

(1) (4a-b²)*(-2b)=4a*(-2b)-b²*(-2b)=-8ab+2b³(2) 2*x²(x-1/2)=2*x²*x-2*x²*1/2=2x³-x²(3) 5ab*(2a-b+0.2)=5ab*2a-5ab*b+5ab*0.2=10a²b-5ab²+ab(4)(2a²...