5х+15- х-7/8 >11/2х-11
40х+120-(х-7)>44х-88
40х+120-х+7>44х-88
39х+127>44х-88
39х-44х>-88-127
-5х>-215
х<43
99-23x+x⁹-9x⁸=-(17x+153-x⁹+9x⁸)
99-23x+x⁹-9x⁸=-17x-153+x⁹-9x⁸
-23x+17x=-153-99
-6x=-252
x= 42
4cos²x+4sinx-1=0
4(1-sin²x) +4sinx-1=0
4-4sin²x+4sinx-1=0
4sin²x-4sinx-3=0
Пусть sinx=t (|t|≤1)
4t²-4t-3=0
D=16+48=64; √D=8
x1=(4+8) /8=1.5
x2=(4-8) /8=-1/2
x1=1.5- не удовлетворяет при |t|≤1
замена
sinx=-1/2
x=(-1)^(k+1) *π/6+πk, k € Z
<span>task/24760498
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cos(arccos(-корень из 3/2)-arcsin 0)
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</span>cos(arccos(-(√<span>3)/2) - arcsin 0) = </span>cos((π -π/3)<span> - 0 )=</span>cos(π -π/3) =cosπ/3 = (√<span>3)/2.
</span>
ответ : (√<span>3)/2.</span>