x²+3x-10=(x+1.5)^2-12.25=(x+1.5+3.5)(x+1.5-3.5)=(x+5)(x-2)
解:原式=(x+1.5)²-1.5²-10=(x+1.5)²-12.25=(x+1.5)²-3.5²=(x-2)(x+5)
x²+3x-10=x²+2*3/2x+(3/2)^2-(3/2)^2-10=(x+3/2)^2-10-(3/2)^2=(x+3/2)^2-31/40
解:(x-2)(x+5)
(x-2)(x+5)