1+ctg^2a=1/sin^2a
1+ctg^2a=1/0,36
Ctg^2a=1/0,36-1
ctg^2a=0,64
ctga=0,8
6ctga=4,8
1,2a·0,8b+1,6c·0,6d+1,5e·0,64f=0,96ab+0,96cd+0,96fe=0,96(ab+cd+ef);
0,96(ab+cd+ef)=96
ab+cd+ef=100 !
A(x+y)+b(x+y)
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Ответ:
5a^2-20b^2=5*(a^2-4b^2)=5*(a-2b)*(a+2b). Ответ: 5*(a-2b)*(a+2b). ^-это степень.
Объяснение:
Для первой степени формула принимает вид:
![y(x)=y(x_0)*\frac{x-x_1}{x_0-x_1}+y(x_1)*\frac{x-x_0}{x_1-x_0}](https://tex.z-dn.net/?f=y%28x%29%3Dy%28x_0%29%2A%5Cfrac%7Bx-x_1%7D%7Bx_0-x_1%7D%2By%28x_1%29%2A%5Cfrac%7Bx-x_0%7D%7Bx_1-x_0%7D)
По условию:
![y(x_0)=y(0.5)=2\\y(x_1)=y(0.7)=2.4\\x_0=0.5\\x_1=0.7](https://tex.z-dn.net/?f=y%28x_0%29%3Dy%280.5%29%3D2%5C%5Cy%28x_1%29%3Dy%280.7%29%3D2.4%5C%5Cx_0%3D0.5%5C%5Cx_1%3D0.7)
Получаем:
![y(x)=2*\frac{x-0.7}{0.5-0.7}+2.4*\frac{x-0.5}{0.7-0.5}=2*\frac{x-0.7}{-0.2}+2.4*\frac{x-0.5}{0.2}=\\=-10(x-0.7)+12(x-0.5)=2x+1](https://tex.z-dn.net/?f=y%28x%29%3D2%2A%5Cfrac%7Bx-0.7%7D%7B0.5-0.7%7D%2B2.4%2A%5Cfrac%7Bx-0.5%7D%7B0.7-0.5%7D%3D2%2A%5Cfrac%7Bx-0.7%7D%7B-0.2%7D%2B2.4%2A%5Cfrac%7Bx-0.5%7D%7B0.2%7D%3D%5C%5C%3D-10%28x-0.7%29%2B12%28x-0.5%29%3D2x%2B1)