Question

4 la puterea x-5 ori 2 la puterea x+1+16=0.

Answer 1

${4}^{x - 5} \times 2 {}^{x + 1} + 16 = 0 \\ 4 {}^{x} \times 4 {}^{ - 5} \times 2 {}^{x} \times 2 + 16 = 0 \\( 2 {}^{2} ) {}^{x} \times \frac{1}{4 {}^{5} } \times 2 {}^{x} \times 2 = - 16 \\ 2 {}^{2x} \times 2 {}^{x} \times \frac{2}{(2 {}^{2} ) {}^{5} } = - 1 6\\ \\ 2 {}^{2x + x} \times \frac{2}{2 {}^{10} } = - 16 \\ \\ 2 {}^{3x} \times \frac{1}{2 {}^{9} } = - {2 }^{4}$${2}^{3x} = - 2 {}^{4} \div \frac{1}{2 {}^{9} } \\ 2 {}^{3x} = - 2 { }^{4} \times 2 {}^{9} \\ 2 {}^{3x} = - 2 {}^{4 + 9} \\ 2 {}^{3x} = - 2 {}^{13}$

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