720: [41- ( 2x -5)] = 2 mũ 3 x 5 80-(4×5 mũ 2 – 3×2 mux3 ) = 2 mũ 10 – (x-4) 05/07/2021 Bởi Valerie 720: [41- ( 2x -5)] = 2 mũ 3 x 5 80-(4×5 mũ 2 – 3×2 mux3 ) = 2 mũ 10 – (x-4)
Giải thích các bước giải: Ta có: \(\begin{array}{l}*)\\720:\left[ {41 – \left( {2x – 5} \right)} \right] = {2^3}.5\\ \Leftrightarrow 720:\left[ {41 – \left( {2x – 5} \right)} \right] = 8.5\\ \Leftrightarrow 720:\left[ {41 – \left( {2x – 5} \right)} \right] = 40\\ \Leftrightarrow 41 – \left( {2x – 5} \right) = 720:40\\ \Leftrightarrow 41 – \left( {2x – 5} \right) = 18\\ \Leftrightarrow 2x – 5 = 41 – 18\\ \Leftrightarrow 2x – 5 = 23\\ \Leftrightarrow 2x = 23 + 5\\ \Leftrightarrow 2x = 28\\ \Leftrightarrow x = 28:2\\ \Leftrightarrow x = 14\\*)\\80 – \left( {{{4.5}^2} – {{3.2}^3}} \right) = {2^{10 – \left( {x – 4} \right)}}\\ \Leftrightarrow 80 – \left( {4.25 – 3.8} \right) = {2^{10 – \left( {x – 4} \right)}}\\ \Leftrightarrow 80 – \left( {100 – 24} \right) = {2^{10 – \left( {x – 4} \right)}}\\ \Leftrightarrow 80 – 76 = {2^{10 – \left( {x – 4} \right)}}\\ \Leftrightarrow 4 = {2^{10 – \left( {x – 4} \right)}}\\ \Leftrightarrow {2^2} = {2^{10 – \left( {x – 4} \right)}}\\ \Leftrightarrow 2 = 10 – \left( {x – 4} \right)\\ \Leftrightarrow \left( {x – 4} \right) = 10 – 2\\ \Leftrightarrow x – 4 = 8\\ \Leftrightarrow x = 8 + 4\\ \Leftrightarrow x = 12\end{array}\) Bình luận
Giải thích các bước giải:
Ta có:
\(\begin{array}{l}
*)\\
720:\left[ {41 – \left( {2x – 5} \right)} \right] = {2^3}.5\\
\Leftrightarrow 720:\left[ {41 – \left( {2x – 5} \right)} \right] = 8.5\\
\Leftrightarrow 720:\left[ {41 – \left( {2x – 5} \right)} \right] = 40\\
\Leftrightarrow 41 – \left( {2x – 5} \right) = 720:40\\
\Leftrightarrow 41 – \left( {2x – 5} \right) = 18\\
\Leftrightarrow 2x – 5 = 41 – 18\\
\Leftrightarrow 2x – 5 = 23\\
\Leftrightarrow 2x = 23 + 5\\
\Leftrightarrow 2x = 28\\
\Leftrightarrow x = 28:2\\
\Leftrightarrow x = 14\\
*)\\
80 – \left( {{{4.5}^2} – {{3.2}^3}} \right) = {2^{10 – \left( {x – 4} \right)}}\\
\Leftrightarrow 80 – \left( {4.25 – 3.8} \right) = {2^{10 – \left( {x – 4} \right)}}\\
\Leftrightarrow 80 – \left( {100 – 24} \right) = {2^{10 – \left( {x – 4} \right)}}\\
\Leftrightarrow 80 – 76 = {2^{10 – \left( {x – 4} \right)}}\\
\Leftrightarrow 4 = {2^{10 – \left( {x – 4} \right)}}\\
\Leftrightarrow {2^2} = {2^{10 – \left( {x – 4} \right)}}\\
\Leftrightarrow 2 = 10 – \left( {x – 4} \right)\\
\Leftrightarrow \left( {x – 4} \right) = 10 – 2\\
\Leftrightarrow x – 4 = 8\\
\Leftrightarrow x = 8 + 4\\
\Leftrightarrow x = 12
\end{array}\)