F(0)=cos (2*0) - 3sin(0)=1
<span>f(п/2)= cos (2*п/2) - 3 sin(п/2)=-4
</span>f(п/6)= cos (2*п/6) - 3 sin(п/6)=-1
Х+2//2-х=2
х+2=2(2-х)
х+2=4-2х
х+2х=4-2
3х=2
х=2/3
Cos(l-b)-cosLcosB=sinLsinB+cosLcosB-cosLcosB= sinLsinB
<span>(10√24-√54)×√6=(20</span>√6-3√6)*√6=120-18=102<span>
(√6-√8):√2=(</span>√3√2-2√2)/√2=√3-2<span>
(3+√5)(√5-4)=3</span>√5-12+5-4√5=-√5-7<span>
(√x-5)(√x+5)=x+5</span>√x-5√x-25=x-25<span>
(√11-√6)²=11-2</span>√11√6+6=17-2√11√6=17-2√66<span>
(√7+2√3)²=7+4</span>√7√3+12=19+4√21<span>
(√2-1)(2+√2+1)=2</span>√2+2+√2-2-√2-1=2√2-1=√8-1
Sin4x-1=0 sin4x=1 4x=П/2 +2Пn x=П/8 +2Пn