Точно не знаю. правильно или нет
1)
<span><span>-2sinxsin8x-2sinxsin2x=0
-2sinx(sin8x+sin2x)=-2sinx*2sin5xcos3x=0
sinx=0⇒x=πn
sin5x=0⇒5x=πn⇒x=πn/5
cos3x=0⇒3x=π/2+πn⇒x=π/6+πn/3
Ответ x=πn/5;x=π/6+πn/3
</span></span><span>
2)
x-y=7
2x+y=8
прибавим
3x=15
x=5
y=5-7=-2
(5;-2)
</span>
F(1)=1^2+1=1+1=2; g(10)=10^2-1=100-1=99. Ответ: f(1)<g(10).
![\dfrac{ \sqrt[3]{a^2\cdot \sqrt[4]{a^6\cdot a^{-1}} } }{\sqrt[4]{a^3\cdot \sqrt[3]{a^2} }} =\dfrac{ \sqrt[3]{a^2\cdot \sqrt[4]{a^{6-1}} } }{\sqrt[4]{a^3\cdot a^{\frac{2}{3}} }} =\dfrac{ \sqrt[3]{a^2\cdot a^{\frac{5}{4}} } }{\sqrt[4]{a^3\cdot a^{\frac{2}{3}} }} =\dfrac{ \sqrt[3]{a^{2+ \frac{5}{4} }} }{ \sqrt[4]{a^{3+ \frac{2}{3} }} }= \dfrac{ \sqrt[3]{a^{\frac{13}{4}}} }{ \sqrt[4]{a^{\frac{11}{3}}} } =\\\\\\=\dfrac{a^{\frac{13}{12}}}{a^{\frac{11}{12}}}=a^{\frac{13}{12}-\frac{11}{12}}=a^{\frac{1}{6}}](https://tex.z-dn.net/?f=+%5Cdfrac%7B+%5Csqrt%5B3%5D%7Ba%5E2%5Ccdot+%5Csqrt%5B4%5D%7Ba%5E6%5Ccdot+a%5E%7B-1%7D%7D+%7D+%7D%7B%5Csqrt%5B4%5D%7Ba%5E3%5Ccdot+%5Csqrt%5B3%5D%7Ba%5E2%7D+%7D%7D+%3D%5Cdfrac%7B+%5Csqrt%5B3%5D%7Ba%5E2%5Ccdot+%5Csqrt%5B4%5D%7Ba%5E%7B6-1%7D%7D+%7D+%7D%7B%5Csqrt%5B4%5D%7Ba%5E3%5Ccdot+a%5E%7B%5Cfrac%7B2%7D%7B3%7D%7D+%7D%7D+%3D%5Cdfrac%7B+%5Csqrt%5B3%5D%7Ba%5E2%5Ccdot+a%5E%7B%5Cfrac%7B5%7D%7B4%7D%7D+%7D+%7D%7B%5Csqrt%5B4%5D%7Ba%5E3%5Ccdot+a%5E%7B%5Cfrac%7B2%7D%7B3%7D%7D+%7D%7D+%3D%5Cdfrac%7B+%5Csqrt%5B3%5D%7Ba%5E%7B2%2B+%5Cfrac%7B5%7D%7B4%7D+%7D%7D+%7D%7B+%5Csqrt%5B4%5D%7Ba%5E%7B3%2B+%5Cfrac%7B2%7D%7B3%7D+%7D%7D+%7D%3D+%5Cdfrac%7B+%5Csqrt%5B3%5D%7Ba%5E%7B%5Cfrac%7B13%7D%7B4%7D%7D%7D+%7D%7B+%5Csqrt%5B4%5D%7Ba%5E%7B%5Cfrac%7B11%7D%7B3%7D%7D%7D+%7D+%3D%5C%5C%5C%5C%5C%5C%3D%5Cdfrac%7Ba%5E%7B%5Cfrac%7B13%7D%7B12%7D%7D%7D%7Ba%5E%7B%5Cfrac%7B11%7D%7B12%7D%7D%7D%3Da%5E%7B%5Cfrac%7B13%7D%7B12%7D-%5Cfrac%7B11%7D%7B12%7D%7D%3Da%5E%7B%5Cfrac%7B1%7D%7B6%7D%7D)
если все верно сделала, то ответ 1)
<span> формула тригон. 1 или по треугольнику.</span><span>По формуле </span>
<span>sinA=+-кор из (1-19/100)=кор из (81/100)=+-0,9. </span><span>1 четверть, значит sinA=0,9. </span>