The value of x in the given equation \( \Large 4^{x}-3^{x-\frac{1}{2}}=3^{x+\frac{1}{2}}-2^{2x-1} \) is:


A) \( \Large \frac{4}{3} \)

B) \( \Large \frac{3}{2} \)

C) \( \Large \frac{2}{1} \)

D) \( \Large \frac{5}{3} \)

Correct Answer:
B) \( \Large \frac{3}{2} \)

Description for Correct answer:

Given equation is

\( \Large 4x-3^{x-\frac{1}{2}}=3^{x+\frac{1}{2}}-2^{2x-1} \)

= \( \Large 2^{2x}+2^{2x-1} = 3^{x+\frac{1}{2}}+3^{x-\frac{1}{2}} \)

= \( \Large 2^{2x} \left(1+\frac{1}{2}\right)=3^{x-\frac{1}{2}} \left(3+1\right) \)

= \( \Large 2^{2x}.\frac{3}{2}=3^{x-\frac{1}{2}}.4 => 2^{2x-3}=3^{x-\frac{3}{2}} \)

taking log:

\( \Large \left(2x-3\right)log2 = \left(x-\frac{3}{2}\right)log3 \)

=> \( \Large 2x log2 - 3 log2 = xlog3-\frac{3}{2}log3 \)

=> \( \Large x log 4 - x log 3 = 3 log^{2} - \frac{3}{2} log 3 \)

= \( \Large xlog \left(\frac{4}{3}\right)= log 8 - log 3\sqrt{3} \)

=> \( \Large log \left(\frac{4}{3}\right)^{x} = log \frac{8}{3\sqrt{3}} \)

=> \( \Large \left(\frac{4}{3}\right)^{x} = \frac{8}{3\sqrt{3}} \)

=> \( \Large \left(\frac{4}{3}\right)^{x} = \left(\frac{4}{3}\right)^{\frac{3}{2}} \)

\( \Large x = \frac{3}{2} \)


Part of solved Quadratic Equations questions and answers : >> Elementary Mathematics >> Quadratic Equations








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