化简:(1)[2b-3+2(a²-1)]-(4a²-3b²)
问题描述:
化简:(1)[2b-3+2(a²-1)]-(4a²-3b²)
(2)(3x²y-xy²)-3(x²y-2xy²)
[2b²-3+2(a²-1)]-(4a²-3b²)
答
化简:
(1)[2b-3+2(a²-1)]-(4a²-3b²)
=2b -3 +2a²-2 -4a²+3b²
=2b -5 -2a²+3b²
(2)(3x²y-xy²)-3(x²y-2xy²)
=3x²y-xy²-3x²y+6xy²
=-xy²+6xy²
= 5 xy²[2b²-3+2(a²-1)]-(4a²-3b²)[2b²-3+2(a²-1)]-(4a²-3b²)
=[2b²-3+2a²-2]-(4a²-3b²)
=2b²-3+2a²-2-4a²+3b²
=5b²-5-2a²