Exponential Equations Solve a 5 ln x 10 b ln 4x 15 c log 2
Exponential Equations
Solve:
a) 5 ln x = 10
b) ln (4x) = 1.5
c) log (2-x) = 0.5
Solution
a) 5 ln x=10
lnx=2
convertint it in exponential form
x=e^2
b) ln 4x=1.5
writing it in exponential form
4x=e^1.5
x=(e^1.5)/4
c) log(2-x)=0.5
writing it in exponential form
2-x=10^0.5
x=2-10^0.5
d) log6(2x+4)=2
converting it in exponential form
2x+4=6^2
2x+4=36
2x=32
x=16
e) log4(x^3 + 37)=3
converting it in exponetial form
x^3 + 37=4^3
x^3=64-37=27
x=3
f) log3(x+5)(x-3)=2
converting it in exponential form we get
(x+5)(x-3)=3^2=9
x^2 +2x-15-9=0
x^2+2x-24=0
(x+6)(x-4)=0
x=-6,4

