7.x-2-1-2x=0 1 4 8. =3(3x-2) 9. 12 21 2 x-1 4 10) 13) ==với (x=−2). x+2 5 = 28 3 16) 2020(-2x2x-3) 8 11) 27 14) (5x+1) 36 49 8 x-5 = 3 x+1 (với x # 5;−1) 12) 2.3 405 3*1. 15) [(-0.5)]- =1. 17) (x+1)*"=(x+1) với xe. 1 1 18) X 2 3 GIẢI HỘ EM VỚI Ạ,EM CẢM ƠN
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69 Tham khảo câu trả lời từ Trợ lý ảo Lazi Sure, let’s go through some of the problems one by one. Here are the solutions: ### 7. \( |x-2| - |1 - 2x| = 0 \) To solve this, consider different cases based on the expressions inside the absolute values: **Case 1:** \( x - 2 \geq 0 \) and \( 1 - 2x \geq 0 \) - \( x \geq 2 \) and \( x \leq \frac{1}{2} \) (no solution) **Case 2:** \( x - 2 \geq 0 \) and \( 1 - 2x < 0 \) - \( x \geq 2 \) - Equation becomes: \( x - 2 - (2x - 1) = 0 \) - Solution: \( x = 1 \) but \( x \geq 2 \) is required (no solution) **Case 3:** \( x - 2 < 0 \) and \( 1 - 2x \geq 0 \) - \( x < 2 \) and \( x \leq \frac{1}{2} \) \(\rightarrow x \leq \frac{1}{2} \) - Equation becomes: \( -(x - 2) - (1 - 2x) = 0 \) - Simplifying: \( -x + 2 - 1 + 2x = 0 \) \(\rightarrow x + 1 = 0 \) \(\rightarrow x = -1 \) - \(-1 \leq \frac{1}{2} \), so valid solution \( x = -1\) **Case 4:** \( x - 2 < 0 \) and \( 1 - 2x < 0 \) - \( x < 2 \) and \( x > \frac{1}{2} \) - Equation becomes: \( -(x - 2) - (2x - 1) = 0 \) - Simplifying: \( -x + 2 - 2x + 1 = 0 \) \(\rightarrow -3x + 3 = 0 \) \(\rightarrow x = 1 \) - \( \frac{1}{2} < 1 < 2 \), so valid solution \( x = 1 \) **Final Solutions:** \( x = -1 \) and \( x = 1 \) ### 10. \( \frac{x-1}{x+2} = \frac{4}{5} \) với \( x \ne -2 \) Cross-multiply to solve for \( x \): \[ 5(x - 1) = 4(x + 2) \] \[ 5x - 5 = 4x + 8 \] \[ 5x - 4x = 8 + 5 \] \[ x = 13 \] ### 15. \([(-0.5)^3]^{-1} = \frac{1}{64} \) Calculate \( (-0.5)^3 \): \[ (-0.5)^3 = -0.125 \] Then, \((-0.125)^{-1}\) should equal \(\frac{1}{-0.125} = -8\), but it seems there might be a typographical error, as it doesn't equal \(\frac{1}{64}\). ### 16. \( 2020^{(-2)(2x-x)} = 1 \) The expression inside simplifies: \[ (-2)(2x-x) = -2x \] For any \( a^0 = 1 \), we need: \[ -2x = 0 \] \[ x = 0 \] Thus, \( x = 0 \). Please let me know if you need help with more problems.