1)0,8 в кубе, в квадрате, просто 0,8
2)2,9, 2,9 в квадрате, 2,9 в кубе... Вроде так.
![\sin x- \sqrt{2} \sin 3x=-\sin 5x\\ \\ \sin x+\sin 5x-\sqrt{2} \sin 3x=0\\ \\ 2\sin \frac{x+5x}{2}\cos \frac{5x-x}{2} -\sqrt{2} \sin3x=0\\ \\ 2\sin3x\cos2x-\sqrt{2} \sin 3x=0\\ \\ \sin3x(2\cos 2x-\sqrt{2} )=0](https://tex.z-dn.net/?f=%5Csin+x-+%5Csqrt%7B2%7D+%5Csin+3x%3D-%5Csin+5x%5C%5C+%5C%5C+%5Csin+x%2B%5Csin+5x-%5Csqrt%7B2%7D+%5Csin+3x%3D0%5C%5C+%5C%5C+2%5Csin+%5Cfrac%7Bx%2B5x%7D%7B2%7D%5Ccos+%5Cfrac%7B5x-x%7D%7B2%7D+-%5Csqrt%7B2%7D+%5Csin3x%3D0%5C%5C+%5C%5C+2%5Csin3x%5Ccos2x-%5Csqrt%7B2%7D+%5Csin+3x%3D0%5C%5C+%5C%5C+%5Csin3x%282%5Ccos+2x-%5Csqrt%7B2%7D+%29%3D0+)
Произведение множителей равен нулю, если хотя бы один из множителей равен нулю.
![\sin3x=0;\,\, \Rightarrow\,\,\, 3x= \pi k,k \in \mathbb{Z};\,\,\, \Rightarrow\,\,\, \boxed{x_1= \frac{\pi k}{3} ,k \in \mathbb{Z}}\\ \\ \\ \cos 2x= \frac{1}{\sqrt{2} } \Rightarrow\,\,\, 2x=\pm \frac{\pi }{4}+2 \pi n,n \in \mathbb{Z};\,\,\, \Rightarrow\,\, \boxed{x_2=\pm \frac{\pi}{8}+ \pi n,n \in \mathbb{Z} }](https://tex.z-dn.net/?f=%5Csin3x%3D0%3B%5C%2C%5C%2C+%5CRightarrow%5C%2C%5C%2C%5C%2C+3x%3D+%5Cpi+k%2Ck+%5Cin+%5Cmathbb%7BZ%7D%3B%5C%2C%5C%2C%5C%2C+%5CRightarrow%5C%2C%5C%2C%5C%2C+%5Cboxed%7Bx_1%3D+%5Cfrac%7B%5Cpi+k%7D%7B3%7D+%2Ck+%5Cin+%5Cmathbb%7BZ%7D%7D%5C%5C+%5C%5C+%5C%5C+%5Ccos+2x%3D+%5Cfrac%7B1%7D%7B%5Csqrt%7B2%7D+%7D+%5CRightarrow%5C%2C%5C%2C%5C%2C+2x%3D%5Cpm+%5Cfrac%7B%5Cpi+%7D%7B4%7D%2B2+%5Cpi+n%2Cn+%5Cin+%5Cmathbb%7BZ%7D%3B%5C%2C%5C%2C%5C%2C+%5CRightarrow%5C%2C%5C%2C+%5Cboxed%7Bx_2%3D%5Cpm+%5Cfrac%7B%5Cpi%7D%7B8%7D%2B+%5Cpi+n%2Cn+%5Cin+%5Cmathbb%7BZ%7D+%7D+)
№92
1) у = (2х -1)²
2) у = 2х² -1
3) у = √(х - 4)
4) у = √х - 4
5) у = 3 - 2√(х² -1)
6) у = (3 - 3√х)³ -1
№93
у = 5х, ⇒ х = у/5
Ответ: у = х/5