Question

calculați
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Answer 1

$4 {}^{x} + 2 {}^{x + 4} - 15 > 0$

$(2 {}^{2} ) {}^{x} + 2 {}^{x + 4} - 15 > 0$

$(2 {}^{2} ) {}^{x} + 2 {}^{x} \times 2 {}^{4} - 15 > 0$

$(2 {}^{x}) {}^{2} + 2 {}^{x} + 2 {}^{4} - 15 > 0$

$(2 {}^{x} ) {}^{2} + 2 {}^{x} \times 16 - 15 > 0$

$t {}^{2} + t \times 16 - 15 > 0$

$2 {}^{x} < - 8 - \sqrt{79}$

$2 {}^{x} > - 8 + \sqrt{79}$

$x > log_{2}( - 8 + \sqrt{79} )$

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