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Solve log(base 2) (x+1) + log (base 2) (x-5)= 4

User Mcbjam
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1 Answer

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(x+1)(x-5)= 2^4=16

x^2 -4x -5 =16

x^2-4x-21=0

x= -3 or 7
but we would choose 7 as the answer as -3 gives negative value at (x+1) and we know that log of negative number is not defined.
User Sahan Amarsha
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