- Exam
- JEE Main
- Subject
- Mathematics
- Chapter
- Basics of Mathematics
JEE Main · Mathematics · Basics of Mathematics
Solve _ 10 ( 2 ^ x +1) + x = _ 10 (6) + x _ 10 (5).
Options
- A4
- B5
- C2
- D1
Correct answer
D. 1
Step-by-step solution
The given expression is&
We know that~\log_{\mathrm{m}}\left(x\right) + \log_{\mathrm{m}}\left(y\right) = \log_{\mathrm{m}} \left(xy\right) & \log_{\mathrm{m}} \left(x\right) + \log_{\mathrm{m}}\left(y\right) = ⇒ \log_{10}\left({2}^{x} +1\right) = x \left(\log_{10} \left(5\right) - \log_{10}\left(10\right)\right) + \log_{10}\left(6\right)⇒ \log_{10} \left({2}^{x} +1\right) = - \log_{10} \left(2\right)x + \log_{10}\left(6\right)⇒ \log_{10} \left({2}^{x} +1\right) + \log_{10} \left({2}^{x}\right) = \log_{10}\left(6\right)⇒ \log_{10} \left[ \left({2}^{x}\right) \left({2}^{x} +1\right)\right] = \log_{10}\left(6\right)⇒ \left({2}^{x}\right) \left({2}^{x} +1\right) = 6⇒ \left({2}^{x}\right)2 + {2}^{x} - 6 = 0⇒ \left({2}^{x} -2\right)\left({2}^{x} +3\right) = 0⇒ {2}^{x} = 2 ⇒ x = 1x = 1