Question

3x - 3x-2 = 72थ्री एक्स माइनस 3 एक्स माइनस टू स्कूल 272 ​

Answer 1

Answer:

${3}^{x} - {3}^{x} . {3}^{ - 2} = 72 \\ {3}^{x}(1 - {3}^{ - 2} ) = 72 \\ {3}^{x} (1 - \frac{1}{ {3}^{2} } ) = 72 \\ {3}^{x} ( \frac{9 - 1}{9} ) = 72 \\ {3}^{x} \times \frac{8}{9} = 72 \\ {3}^{x} = \frac{72 \times 9}{8} \\ {3}^{x} = 9 \times 9 \\ {3}^{x} = {3}^{2} \times {3}^{2} \\ {3}^{x} = {3}^{4} \: \: \: (base \: are \: same) \\ \\ x = 4 \: \: (answer)$