化简在求值-5y²+{2xy-[y²+x²-(1-y²)+2xy]+3x²}其中x=3/2,y=-2

问题描述:

化简在求值-5y²+{2xy-[y²+x²-(1-y²)+2xy]+3x²}其中x=3/2,y=-2

-5y²+{2xy-[y²+x²-(1-y²)+2xy]+3x²}
=-5y²+{2xy-y²-x²+(1-y²)-2xy+3x²}
=-5y²-2y²+2x²+1
=-7y²+2x²+1
=-7*(-2)²+2*(3/2)²+1
=-28+9/2+1
=-45/2