16(х^2-1)-(16х^2-56х+49)=0
16х^2-16-16х^2+56х-49=0
56х=49+16
56х=65
х=65:56
х=1,16
2aa+а*3а+а2=2a^2+3a^2+2a^2=7a^2
А) (a-b)a + a(2-x) - x(2-b) = a*(a-b+2-x)
<span>б) (x-2)(x+3) + 2(x+1) = x^2+x-6+2x+2=x^2+3x-4=(x-1)(x+4)</span>
Преобразовываем:2(1-cos^2x)+3cos^2x-2=0
2-2cos^2x+3cos^2x-2=0
Cos^2x=0
Cosx=0
P/2+pn,n & z