Wednesday, December 1, 2010

Today in class we did review questions from exponents and logarithms review sheet.

Place logarithm with base 10 in both sides. Then move the exponents in the front of logarithm. Multiply with exponent in brackets if in brackets. Take logs with x to the one side and rest of all to the other side. Factor the x out using bracket. Then divide both sides with whatever is in the bracket with the x. Then solve for x.
Example: Solve the following equation by algebraically and state your answer up to 3 decimal place.
3^x+1 = 4(5^x)

3^x+1 = 4(5^x)
Log3^x+1 = log4 + log5^x
(X+1) log3 = log4 + xlog5
Xlog3 + log3 = log4 + xlog5
Xlog3 - xlog5 = log4 - log3
X (log3 – log5) = log4 - log3
X (log3 – log5)/ log3 – log5 = log4 - log3/ log3 – log5
X = log4 - log3/ log3 – log5
X = - 0.563

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