![x^{2} +2\sqrt{x^{2}-6x } \leq 6x+24\\x^{2} -6x+2\sqrt{x^{2}-6x } \leq24 x^{2} +2\sqrt{x^{2}-6x } \leq 6x+24\\x^{2} -6x+2\sqrt{x^{2}-6x } \leq24](https://tex.z-dn.net/?f=x%5E%7B2%7D%20%2B2%5Csqrt%7Bx%5E%7B2%7D-6x%20%7D%20%5Cleq%206x%2B24%5C%5Cx%5E%7B2%7D%20-6x%2B2%5Csqrt%7Bx%5E%7B2%7D-6x%20%7D%20%5Cleq24)
Пусть x^2 - 6x = t :
ОДЗ : t ≥ 0
Рассмотри 2 случая :
1. t ≤ 24
![(2\sqrt{t} )^{2} \leq (24-t)^{2} \\4t\leq t^{2} -48t+576\\t^{2} -52t+576\geq 0 \\(t-16)(t-36) \geq 0\\ (2\sqrt{t} )^{2} \leq (24-t)^{2} \\4t\leq t^{2} -48t+576\\t^{2} -52t+576\geq 0 \\(t-16)(t-36) \geq 0\\](https://tex.z-dn.net/?f=%282%5Csqrt%7Bt%7D%20%29%5E%7B2%7D%20%5Cleq%20%2824-t%29%5E%7B2%7D%20%5C%5C4t%5Cleq%20%20t%5E%7B2%7D%20-48t%2B576%5C%5Ct%5E%7B2%7D%20-52t%2B576%5Cgeq%200%20%5C%5C%28t-16%29%28t-36%29%20%5Cgeq%20%200%5C%5C)
+ - +
---------------[16]------------[36]--------------------
t ∈ (-∞; 16] U [36 ; +∞)
t ≤ 24
t ≥ 0
------------------
t ∈ [0 ; 16]
2. t > 24 :
t ∈ ∅
________________
Общее : t ∈ [0 ; 16]
![x^{2} -6x \geq 0\\x(x-6) \geq 0\\ x^{2} -6x \geq 0\\x(x-6) \geq 0\\](https://tex.z-dn.net/?f=x%5E%7B2%7D%20-6x%20%5Cgeq%200%5C%5Cx%28x-6%29%20%5Cgeq%200%5C%5C)
x ∈ (-∞ ; 0] U [6 ; +∞)
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![x^{2} -6x \leq 16\\x^{2} -6x-16 \leq 0\\(x+2)(x-8} ) \leq 0 x^{2} -6x \leq 16\\x^{2} -6x-16 \leq 0\\(x+2)(x-8} ) \leq 0](https://tex.z-dn.net/?f=x%5E%7B2%7D%20-6x%20%5Cleq%2016%5C%5Cx%5E%7B2%7D%20-6x-16%20%5Cleq%200%5C%5C%28x%2B2%29%28x-8%7D%20%20%29%20%5Cleq%200)
x ∈ [-2, 8]
Объединим решения
Ответ : x ∈ [-2 ; 0] U [6 ; 8]