jika log 2 =a dan log3=b,maka log72 =

log2 = a, dan log3 = b
log72 = log( 8 x 9)
log72 = log(2³ x 3²)
         =3. log2 + 2.log3
         =3a + 2b

moga membantu ^_^

log 72 = log 3^2 x 2^3
= log 3^2 + log 2^3
= b^2 + a^3