(1)2x^2+3x(2)3x^2+4x=3(3)2x^2-5x+3=0(4)4x^2+25=20x
问题描述:
(1)2x^2+3x(2)3x^2+4x=3(3)2x^2-5x+3=0(4)4x^2+25=20x
答
(1)2x^2+3x=0 ?x(2x+3)=0x₁=0、x₂=-3/2(2)3x^2+4x=3 3x²+4x-3=0Δ=16+36=52x=(-4±√52)/6(3)2x^2-5x+3=0(x-1)(2x-3)=0x₁=1、x₂=3/2(4)4x^2+25=20x 4x²-20x+25=0 (2x-5)²=...