1) 1 - 5x² = 1 - 5 * (- 4)² = 1 - 5 * 16 = - 79
2) y⁷ * y¹² = y⁷⁺¹² = y¹⁹
y²⁰ : y⁵ = y²⁰⁻⁵ = y¹⁵
(y²)⁸ = y¹⁶
( 2y)⁴ = 16y⁴
a) - 2ab³ * 3a² * b⁴ = - 6a¹⁺²b³⁺⁴ = - 6a³b⁷
б) (-2a⁵b²)³ = - 8a¹⁵b⁶
5)
![\frac{25^{2}*5^{5}}{5^{7} } =\frac{(5^{2})^{2}*5^{5}}{5^{7} } =\frac{5^{4}* 5^{5} }{5^{7} }=5^{4+5-7} =5^{2} =25](https://tex.z-dn.net/?f=%5Cfrac%7B25%5E%7B2%7D%2A5%5E%7B5%7D%7D%7B5%5E%7B7%7D%20%7D%20%3D%5Cfrac%7B%285%5E%7B2%7D%29%5E%7B2%7D%2A5%5E%7B5%7D%7D%7B5%5E%7B7%7D%20%7D%20%3D%5Cfrac%7B5%5E%7B4%7D%2A%205%5E%7B5%7D%20%7D%7B5%5E%7B7%7D%20%7D%3D5%5E%7B4%2B5-7%7D%20%3D5%5E%7B2%7D%20%3D25)
Ответ:
<em>0,25.</em>
Объяснение:
<em>2⁻⁵ : (2³ : 2⁶) = 2⁻⁵ : 2³⁻⁶= 2⁻⁵ : 2⁻³= 2⁻⁵⁻⁽⁻³⁾= 2⁻⁵⁺³= 2⁻²= 1/2²= 1/4 = 0,25</em>
![x^3-8x^2+16x=x^2*x-8x*x+16*x=](https://tex.z-dn.net/?f=x%5E3-8x%5E2%2B16x%3Dx%5E2%2Ax-8x%2Ax%2B16%2Ax%3D)
выносим общий множитель
![x(x^2-8x+16)=x(x^2-2*x*4+4^2)=](https://tex.z-dn.net/?f=x%28x%5E2-8x%2B16%29%3Dx%28x%5E2-2%2Ax%2A4%2B4%5E2%29%3D)
используем формулу квадрата разности
![A^2-2AB+B^2=(A-B)^2](https://tex.z-dn.net/?f=A%5E2-2AB%2BB%5E2%3D%28A-B%29%5E2)
получим
![x(x-2)^2](https://tex.z-dn.net/?f=x%28x-2%29%5E2)
Y`=(lncos(1+2x))`*e^x+(e^x)`*lncos(1+2x)+(2/x²)`=
=-2sin(1+2x)e^x/cos(1+2x)+e^x*lncos(1+2x)-4/x³=
=-2e^x*tg(1+2x)+<span>e^x*lncos(1+2x)-4/x³</span>