<span>x^4 - 20x^2 + 64 = 0
x</span>²=t
<span>t</span>²-20t+64=0
<span>D=b</span>²-4ac=20²-4*1*64=400-256=144
<span>t1=-b-</span>√D / 2a = 20-12/2=8/2=4
<span>t2=-b+</span>√D/2a=20+12/2=32/2=16
x²=4 x²=16
<span>x1=2 x3=4
x2=-2 x4=-4
Ответ: х1=-2, х2=2, х3=-4, х4=4</span>
√15876 = √(2² * 3⁴ * 7² ) = 2 * 3² * 7 = 126
<span>(√6+√3)√12-2√6х√3=6√2+6-6√2x=6√2(1-√x)+6<span>умножить на√3=6√6(1-√x)+6√3</span></span>
Х 4 – 13Х 2 + 36= 0
.........................................