3^x . 3^2 + 9^x . 9 = 810
Matematika
sindysp18
Pertanyaan
3^x . 3^2 + 9^x . 9 = 810
2 Jawaban
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1. Jawaban Anonyme
3^x . 3^2 + 9^x . 9 = 810
bagi 9
3^x + 9^x = 90
3^x + 3^2x - 90 = 0
(3^x + 10)(3^x - 9) = 0
3^x - 9 = 0
3^x = 9
x = 2
Nilai x yg memenuhi : x = 2 -
2. Jawaban syifajs
3^x . 3² + 9^x . 9 = 810
☞ 3^x . 9 + (3²)^x . 9 = 810
☞ 3^x . 9 + (3^x)² . 9 = 810
Gunakan permisalan, misalkan 3^x = s
☞ s . 9 + s² . 9 = 810
Maka s = 9 dan s = -10
Sehingga
☞ 3^x = 9 ☞ x = 2
☞ 3^x = -10
HP = {2}