1)x^2-5x+6=0;
x1+x2=5 U x1*x2=6
x1=2 U x2=3
2)4x^2-12x+9=0;
(2x-3)²=0
2x=3
x=1,5
3)x^2+2x-24=0;
x1+x2=-2 U x1*x2=-24
x1=-6 U x2=4
4)x^2+9x+14=0;
x1+x2=-9 U x1*x2=14
x1=-7 U x2=-2
5)x^2-7ax+12a^2=0
x1+x2=7a U x1*x2=12a²
x1=3a U x2=4a
Решение смотри на фотографии
Cost = 3/4 cos(t/2) = ((1 + cost)/2)^(1/2) = ((1 + 3/4)/2)^(1/2) = (7/8)^(1/2) = (7^(1/2))/(2*(2^(1/2))) sin(t/2) = (1 - cos^2(t/2))^(1/2) = (1 - 7/8)^(1/2) = 1/(8^(1/2)) = 1/(2*(2^(1/2))) tg(t/2) = sin(t/2)/cos(t/2) = (1/(2*(2^(1/2))))/((7^(1/2))/(2*(2^(1/2)))) = 1/(7^(1/2)) ctg(t/2) = 1/tg(t/2) = 7^(1/2)<span> </span>