(2t+3)的平方=3(2t+3) (3-y)的平方+y的平方=9 (x+1)的平方=3x+2
问题描述:
(2t+3)的平方=3(2t+3) (3-y)的平方+y的平方=9 (x+1)的平方=3x+2
用适当的方法解下列一元二次方程!
答
(1)(2t+3)^2=3(2t+3)(2t+3)^2-3(2t+3)=0(2t+3)(2t+3-3)=0 t=-3/2或0(2)(3-y)^2+y^2=99-6y+y^2+y^2=92y^2-6y=0y(y-3)=0y=0或3(3)(x+1)^2=3x+2x^2+2x+1=3x+2x^2-x-1=0X^2-X+1/4-5/4=0(X-1/2)^2=5/4X=(±根5+1)/...