No 14 sama no 15 pembahasannya ya Makasih sebelumnya

Cukup menggunakan sifat dasar eksponen dan logaritma

14) sifat logaritma :
1) (xlog b)/(xlog a) = alog b
2) a^(alog b) = b

a = (5log3)/(5log4) = 4log3 = (2^2)log3 = 1/2 . 2log3

2^a = 2^(1/2 . 2log3) = (2^(2log3))^1/2 = (3)^1/2 = √3

(2^3a - 2^-3a)/(2^a + 2^-a)
= ((2^a)^3 - 1/(2^a)^3) / (2^a + 1/(2^a))
= (√3^3 - 1/(√3^3)) / (√3 + 1/√3)
= (3√3 - 1/(3√3)) / (√3 + 1/√3) . (√3)/(√3)
= (9 - 1/3) / (3 + 1)
= (26/3) / 4
= 26/12
= 13/6

15) blog a = 2 => a = b^2 => a^3 = (b^2)^3 => a^3 = b^6
blog (c + 3) = 6 => (c + 3) = b^6 => (c + 3) = a^3
alog (2c + 1) = 3
=> (2c + 1) = a^3
=> (2c + 1) = (c + 3)
=> 2c - c = 3 - 1
=> c = 2