1) 4ˣ + 2ˣ - 2 = 0
Сделаем замену : 2ˣ = m , m > 0
m² + m - 2 = 0
D = 1² - 4 * (- 2) = 1 + 8 = 9 = 3²
![m_{1}=\frac{-1+3}{2}=1\\\\m_{2}=\frac{-1-3}{2}=-2<0\\\\2^{x}=1\\\\2^{x}=2^{0}\\\\x=0\\\\2^{x}=-2\\\\x\in \oslash](https://tex.z-dn.net/?f=m_%7B1%7D%3D%5Cfrac%7B-1%2B3%7D%7B2%7D%3D1%5C%5C%5C%5Cm_%7B2%7D%3D%5Cfrac%7B-1-3%7D%7B2%7D%3D-2%3C0%5C%5C%5C%5C2%5E%7Bx%7D%3D1%5C%5C%5C%5C2%5E%7Bx%7D%3D2%5E%7B0%7D%5C%5C%5C%5Cx%3D0%5C%5C%5C%5C2%5E%7Bx%7D%3D-2%5C%5C%5C%5Cx%5Cin+%5Coslash)
Ответ : 0
2) 9ˣ + 2 * 3ˣ - 3 = 0
Сделаем замену : 3ˣ = m , m > 0
m² + 2m - 3 = 0
D = 2² - 4 * (- 3) = 4 + 12 = 16 = 4²
![m_{1} =\frac{-2+4}{2}=1\\\\m_{2}=\frac{-2-4}{2}=-3<0\\\\3^{x}=1\\\\3^{x}=3^{0}\\\\x=0\\\\3^{x}=-3\\\\x\in \oslash](https://tex.z-dn.net/?f=m_%7B1%7D+%3D%5Cfrac%7B-2%2B4%7D%7B2%7D%3D1%5C%5C%5C%5Cm_%7B2%7D%3D%5Cfrac%7B-2-4%7D%7B2%7D%3D-3%3C0%5C%5C%5C%5C3%5E%7Bx%7D%3D1%5C%5C%5C%5C3%5E%7Bx%7D%3D3%5E%7B0%7D%5C%5C%5C%5Cx%3D0%5C%5C%5C%5C3%5E%7Bx%7D%3D-3%5C%5C%5C%5Cx%5Cin+%5Coslash)
Ответ : 0
<span>найдите площадь круга вписанного в равносторонний треугольник со стороной 6см
S=</span>π r², r=1/3 h , r²= h²/9 ⇔S=π h²/9<span>
</span> h² = a²-(a/2)², a=6 ⇒ h² = 6²-(6/2)²=(6-3)(6+3)=27 ⇔S=π <span>27/9=3</span>π
Sin5xcos4x - cos5xsin4x = 0
sin(5x - 4x) = 0
sinx = 0
x = πk, k∈z
Х²+bx-24=0
x1=-2;x2=?;b=?
по теорема Виеета
1)x1*x2=-24
-2*x2=-24
x2=12
2)x1+x2=-b
-b=-2+12
b=-10