Question 1110675: Topic solving logarithmic
solve the equation
Log base 3 (10x^2-x-2)=2+2log base 3 x
(Please help me do one of my assignment question) Found 2 solutions by josgarithmetic, ikleyn:Answer by josgarithmetic(39620) (Show Source):
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10x^2 - x - 2 = 9x^2
x^2 - x - 2 = 0
(x-2)*(x+1) = 0
The roots to the last equation are x= 2 and x= -1.
The value x= -1 does not work as the solution to the original equation,
since is not defined.
The value x= 2 is the solution: both the left side and the right side of the original equation are DEFINED at x= 2.
Answer. The given equation has one and only one solution x= 2.
Check. The left side is = = = .
The right side is the same value.