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<span>6x^2+х =0
x(6x+1)=0
x=0
6x+1=0
6x=-1
x=-1/6
</span>
2Cos²x - 5Cosx + 3 = 0
Сделаем замену :
Cosx = m , - 1 ≤ m ≤ 1
2m² - 5m + 3 = 0
D = (- 5)² - 4 * 2 * 3 = 25 - 24 = 1
1)4(x+2)+10x=22
4x+8+10x=22
14x+8=22
14x=22-8
14x=14
x=14÷14
x=1