How do you simplify ln(8x)^(1/2)+ln4x^2-ln(16x)^(1/2)?

2 Answers
May 17, 2018

ln(8x)^(1/2)+ln4x^2-ln(16x)^(1/2)=2lnx+3/2ln2

Explanation:

We will use identities lna+lnb=ln(a*b), lna-lnc=ln(a/c) and lna^n=nlna.

Hence ln(8x)^(1/2)+ln4x^2-ln(16x)^(1/2)

= ln(((8x)^(1/2)*4x^2)/(16x)^(1/2))

= ln((8^(1/2)color(red)(x^(1/2))*4x^2)/(16^(1/2)color(red)(x^(1/2))))

= ln((8^(1/2)*4x^2)/16^(1/2))

= ln((2^2x^2)/2^(1/2))

= ln2^2+lnx^2-ln2^(1/2)

= 2ln2+2lnx-1/2ln2

= 2lnx+3/2ln2

May 17, 2018

color(indigo)(=> (3/2) ln 2 + 2 ln x

Explanation:

log m + log n = log (mn)

log m - log n = log (m/n)

Given : ln (8x)^(1/2) + ln (4x^2) - ln(16x)^(1/2)

=> ln ((8x)^(1/2) * (4x^2)) - ln (16x)^(1/2)

=> ln ((2sqrt2*4*x^(1/2)*x^2)/(16x)^(1/2))

=> ln ((cancel(8)^2sqrt2 * cancel((x)^(1/2)) * x^2) / (cancel4 * cancel((x)^(1/2))))

=> ln (2sqrt2x^2)

=> ln (2^(3/2)) + ln x^2

color(indigo)(=> (3/2) ln 2 + 2 ln x