<span>а) (3у</span>²<span>-3у+1)-(4у-2)= 3y</span>²-3y+1-4y+2=3y²-7y+3
<span>б) 4b</span>³(3b²+b)=4b^4(3b+1)<span>
</span>
80 * 2^(-3) - 2^2 = 80 / (2^3) - 4 = 80 / 8 - 4 = 10 - 4 = 6
C = 2
r.
C = 2*3,14*10,97 = 6,28*10,97 = 68,8916 ≈ 68,89.
-а+1,5а+<em>0,1в</em>-а-<em>0,1в</em>=-0,5а
выделенное сократили
4(1+cosx)=3sin²x/2сosx/2
cos²x/2=1+cosx/2 |*2
2cos²x/2=1+cosx
4(2cos²x/2)=3sin²x/2*cosx/2
8cos²x/2-3sin²x/2*cosx/2=0
cosx/2(8cosx/2-3sin²x/2)=0
cosx/2=0
x/2=п/2+пn,n€z
x=п+2пn,n€z
8cosx/2-3sin²x/2=0
8cosx/2-3(1-cos²x/2)=0
3cos²x/2+8cosx/2-3=0
cosx/2=t
3t²+8t-3=0
D=64-4*3*(-3)=100
t1=-8+10/6=1/3
t2=-8-10/6=-18/6=-3
cosx/2=1/3
x/2=+-arccos1/3+2пn,n€z
x=+-2arccos1/3+4пn,n€z
cosx/2=-3
нет решения .
Ответ: x=п+2пn,n€z; x=+-2arccos1/3+4пn,n€z