x + y = П/4
sinx/cosx + siny/cosy = 1 | x,y <> П/2 + Пk
sinx*cosy + siny*cosx = cosx*cosy
sin(x+y) = cosx*cosy
cosx*cosy = sin(П/4)
cosx*cos(П/4-x) = sin(П/4)
cosx*(cos(П/4)*cos(x) + sin(П/4)*sin(x)) = sin(П/4) | cos(П/4) = sin(П/4)
cosx*(cosx+sinx) = 1
cos^2x + cosx*sinx = 1
cosx*sinx - sin^2x = 0
sinx*(cosx - sinx) = 0
sinx = 0 -> x = Пk, y = П/4 - Пk
cosx = sinx -> x = П/4 - Пk, y = Пk
cos^2x = sinx*siny
sin^2x = cosx*cosy
1 = sinx*siny + cosx*cosy
1 = cos(x-y)
x-y = П/2 + 2Пk, y = x + П/2 + 2Пk
cos^2x = sinx*sin(x+П/2) = sinx*cosx -> cosx = 0 | cosx = sinx
sin^2x = cosx*cos(x+П/2) = cosx*(-sinx) -> sinx = 0 | sinx = -cosx
--> cosx = 0 | sinx = 0 --> x = Пn/2, y = П(n+1)/2 + 2Пk
cosx*sqrt(cos2x) = 0 | cos2x >= 0
2sin^2x = cos(2y-П/3) | 2sin^2x <= 1
cosx*sqrt(cos^2x - sin^2x) = 0
cosx*sqrt(1 - 2sin^2x) = 0
cosx*sqrt(1 - cos(2y-П/3)) = 0
cosx = 0 -> x = П/2 + Пk - > 2sin^2x > 1 - не подходит
cos(2y-П/3) = 1 - > 2y - П/3 = П/2 + 2Пk -> y = 5П/12 + Пk | cos2x = 1 - 2sin^2x = 1 - cos(2y-П/3) = 0 -> x = П/4 + Пn/2
--> x = П/4 + Пn/2, y = 5П/12 + Пk/2
Объяснение:
№1
а) √50 > 7
√50 > √7²
√50 > √49
б) 4√6 > 3√7
√4²*6 > √3²*7
√16*6 > √9*7
√96 > √63
№2
а) √(196 * 0,64) = √(14²*(0,8)²) = 14 * 0,8 = 11,2
б) √(72*0,5)=√36=√6² = 6
в) 
г) √(-2)⁶ = √((-2)³)²=(-2)³= - 8
№3
а) (√3+√2)² = (√3)²+ 2 *√3*√2 + (√2)²= 3 + 2√6 + 2 = 5 +2√6
б) (4 - √5)(4 + √5) = 4² - (√5)² = 16 - 5 = 11
в) 5√12 - 2√27 - 3√3 = 5√(4*3) - 2√(9*3) - 3√3 = 5√(2²*3) - 2√(3²*3) - 3√3 = 5*2√3 - 2*3√3 - 3√3= 10√3 - 6√3 - 3√3 = √3
№4
√(72*а⁵) = √(36*2 * а⁴*а)= √(6²*2 * (а²)² * а) = 6*а²*√(2а)
№5

№6

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