Pertanyaan

Jika 39 3 x + 1 + 3 x + 2 + 3 x + 3 = 27 , nilai x yang memenuhi adalah ....

Jika $\frac{3 ^{x + 1} + 3 ^{x + 2} + 3 ^{x + 3}}{39} = 27$ , nilai $x$ yang memenuhi adalah ....

R. Hajrianti

Master Teacher

Mahasiswa/Alumni Universitas Pendidikan Indonesia

Jawaban terverifikasi

Jawaban

jawaban yang benar adalah B.

Pembahasan

Ingat kembali bentuk persamaan eksponen berikut: Maka: Jadi, jawaban yang benar adalah B.

Ingat kembali bentuk persamaan eksponen berikut:

straight a to the power of straight f open parentheses straight x close parentheses end exponent equals straight a to the power of straight m comma space straight a greater than 0 space rightwards arrow space straight f open parentheses straight x close parentheses equals straight m

Maka:

$table attributes columnalign right center left columnspacing 0px end attributes row cell fraction numerator 3 to the power of x plus 1 end exponent plus 3 to the power of x plus 2 end exponent plus 3 to the power of x plus 3 end exponent over denominator 39 end fraction end cell equals 27 row cell fraction numerator 3 to the power of x times 3 to the power of 1 plus 3 to the power of x times 3 squared plus 3 to the power of x times 3 cubed over denominator 39 end fraction end cell equals 27 row cell 3 to the power of x times 3 plus 3 to the power of x times 9 plus 3 to the power of x times 27 end cell equals cell 27 times 39 end cell row cell 3 to the power of x times up diagonal strike 39 end cell equals cell 27 times up diagonal strike 39 end cell row cell 3 to the power of x end cell equals 27 row cell 3 to the power of x end cell equals cell 3 cubed end cell row x equals 3 end table$

Jadi, jawaban yang benar adalah B.