Решите уравнения 1) 2x^2-5x+3=0 2) 2x^2-7x-4=0
2x^2-5x+3=0 D=(-5)^2-4*2*3=25-24 X=5+1/4=3/2 X=5-1/4=1 2x^2-7x-4=0 D=(-7)^2-4*2*(-4)=81 X=7+9/4=4 X=7-9/4=-1/2
2х²-5x=3=0 a=2 b= -5 c=3 D=b²-4*a*c=(-5)²-4*2*3 = 25-24 =1 D=1 X12 = - b +- √D ------------ 2*a X1 = 5 + √1 5+1 6 1.5 или 5 ---------- = -------- = ------- = 1---------- 2*2 4 4 10 X2 = 5-√1 = 4 ------- ----- = 1 2*2 4 X12=1,5 и 1