А DOE
b COE
в KOD
г BOD
д AOK и AOC
AOK 65 BOC 80 KOE 80 DOE 35
1) cos^2 a = 1- sin^2 a
<span>cos^2 a = 1 - (1/3)^2
</span>cos^2 a = 1 - 1/9
cos^2 a = +- корень (8/9)
соs a = +корень8 / 3
2) <span>log два 32 +logтри27 - 7 = 5 + 3 -7=1
3)</span><span>logдва 16+logпять25-logтри81 = 4 + 2 - 4=2</span>
280 - x = 340 - 230
280 - x = 110
- x = 110 - 280
- x = - 170
x = 170