3х+4х+8х=120
15х=120
х=8
распределение будет
24:32:64
log2(x+5)=log2(3x-1)+log2(x-1)
<span>2cos^2x-2sin2x+1=0.
2cos^2x - 4sinxcosx + 1 = 0
2cos^2x - 4</span><span>sinxcosx + sin^2x + cos^2x = 0</span>
sin^2x - 4sinxcosx + 3cos^2x = 0 /: cos^2x не рав. 0
tg^2x - 4tgx +3=0
(tgx - 1 )(tgx - 3 ) = 0
1) tgx = 1 ==> x = pi/4 +pik, k c Z
2) tgx = 3 ===> x = arctg(3) +pik, k c Z
2/3v7 = 2v7/28
4/(v11 +3) = 4(v11 - 3)/2= 2(v11 - 3)=2v11-6