3369, 3396, 3399, 3366, ой сорри не те
=(4x)²+2*4x*5+5²=(4x)²+40x+5²=(4x+5)².
2,05х(6)-3,07х(6)+1,03(:)=0,01;
2,05х(6)-2,04х(6)=0,01;
0,01х(6)=0,01;
х(6)=1;
х=1.
Уравнение касательной к графику: ![y = f'(x_{0} )(x - x_{0} ) +f(x_{0} )](https://tex.z-dn.net/?f=y%20%3D%20f%27%28x_%7B0%7D%20%29%28x%20-%20x_%7B0%7D%20%20%29%20%2Bf%28x_%7B0%7D%20%29)
- сложная функция: косинус - внешняя функция, а 6x - внутренняя.
![f'(x) = 2*cos^{2-1} (6x) * (cos(6x)'*(6x)' = 2*cos(6x)*( -sin(6x))*6 = -12*cos(6x)*sin(6x) = -6*sin(12x);\\](https://tex.z-dn.net/?f=f%27%28x%29%20%3D%202%2Acos%5E%7B2-1%7D%20%286x%29%20%2A%20%28cos%286x%29%27%2A%286x%29%27%20%3D%202%2Acos%286x%29%2A%28%20-sin%286x%29%29%2A6%20%3D%20-12%2Acos%286x%29%2Asin%286x%29%20%3D%20-6%2Asin%2812x%29%3B%5C%5C)
![f'(x_{0} ) = -6 *sin (12\pi /24) = -6*sin(\pi /2) = -6;\\f(x_{0} ) = cos^{2}(6\pi /24) = cos^{2}(\pi /4) = \frac{1}{2} ;\\y = -6*(x - \pi /24) + \frac{1}{2}](https://tex.z-dn.net/?f=f%27%28x_%7B0%7D%20%29%20%3D%20-6%20%2Asin%20%2812%5Cpi%20%20%2F24%29%20%3D%20-6%2Asin%28%5Cpi%20%2F2%29%20%3D%20-6%3B%5C%5Cf%28x_%7B0%7D%20%29%20%3D%20cos%5E%7B2%7D%286%5Cpi%20%2F24%29%20%3D%20cos%5E%7B2%7D%28%5Cpi%20%2F4%29%20%3D%20%5Cfrac%7B1%7D%7B2%7D%20%20%20%20%3B%5C%5Cy%20%3D%20-6%2A%28x%20-%20%5Cpi%20%2F24%29%20%2B%20%5Cfrac%7B1%7D%7B2%7D)