<span>-20sin1°/ sin359°=-</span>20sin(360-359)/ sin359°=-20sin<span><span>359°</span>/ sin359°</span>=-20
<span>2а^2 - х^2 - ах - а + х
a^2+ a^2 - x^2- ax - a +x
a^2-ax+a^2-a-x^2+x
a(a-x)+a(a-1)-x(x-1)
(a-x)(a-1)(x-1)(a+a-x)
<span>(a-x)(a-1)(x-1)(2a-x)</span></span>
А) (3а^2 - 2^2)- (a^2-8^2)= 2a^2-60
б) (3*(-1) - 2)(3*(-1) + 2)-(-1 -8)(-1+8)=-58
<span>(х+5)(30-х)-х(35-х)=50</span>
<span>30х-х^2+150-5х-35х+х^2=50</span>
<span>-10х=-100</span>
<span>х=10</span>
<span>ответ:10</span>
Решение:
x^2=1/√2
x1,2=(+)(-)(1/√√2)