Simplify:
23 · 24
When multiplying exponential expressions with the same base, add the exponents!
23 · 24 = 23+4 = 27 = 128
Solve for x:
2x = 25
Since the bases are the same, set the exponents equal!
x = 5
Write log2 8 = 3 in exponential form
23 = 8
Expand:
log (xy)
log (xy) = log x + log y
Condense:
log(x) + log(y)
log x + log y = log(xy)
Simplify:
35 / 32
When dividing exponential expressions with the same base, subtract the exponents!
35 / 32 = 35-2 = 33 = 27
Solve for x:
3x+1=34
x + 1 = 4 ----> x=3
Write 104 = 10,000 in logarithmic form
log10 10,000 = 4.
Expand:
log (x/y)
log (x/y) = log x − log y
Condense:
log(x) − log(y)
log x − log y = log (x / y)
Simplify:
(x2 · y3)4
Apply the power to each factor inside the parentheses!
(x2 · y3)4 = x2x4 · y3x4 = x8 · y12
Solve for x:
52x = 58
2x = 8 ----> x = 4
Write log5 25 = 2 in exponential form
52 = 25
Expand:
log(x2y3)
log(x2y3) = logx2 + logy3 = 2 logx + 3 logy
Condense:
2log(x) + 3log(y)
2logx + 3logy = logx2 +logy3 = log(x2y3)
Simplify:
(23 · 42)2
First, express 4 as 22
23 · 42 = 23 · (22)2 = 23 · 24 = 23+4 =27
Then raise to the power of 2
(27)2 = 27x2 = 214 = 16,384
Solve for x:
73x+1 = 7x+7
3x + 1 = x + 7 ---> 2x = 6 ---> x = 3
Write 3x = 81 in logarithmic form
and solve for x
log3 81 = x
Since 81 = 34, then
x = 4
Expand:
log (a3b2 / c)
log (a3b2 / c) = loga3 + logb2 − logc
= 3 loga + 2 logb − logc.
Condense:
1/2 log(a) + log(b) − log(c)
1/2 loga +logb − logc
= loga1/2 + logb − logc
= log (a1/2b / c)
Simplify:
(3x2)3 / (9x4)2
(3x2)3 = 33x2x3 = 27x6
(9x4)2 = 92x4x2 = 81x8
Now divide:
27x6 / 81x8 = 27x6-8/81 =1x-2/3 = 1/3x2
Solve for x:
22x / 2x+3 = 24
22x - (x+3) = 2x-3 = 24 --> x−3 = 4 --> x = 7
Write logb (x2) = 3 in exponential form
and solve for x in terms of b
b3 = x2 ---> x = ±b3/2
Expand:
log ((xy)5 / z3)
log ((xy)5 / z3) = 5(logx + logy) − 3 logz
= 5 logx + 5 logy − 3 logz.
Condense:
log(x2) − 3log(y) + 1/2log(z)
logx2 − 3logy + 1/2logz
= 2logx − 3logy + logz1/2
= log (x2√z / y3)