SOLUTION: log2(x + 1) + log2(x + 2) = log2 6

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Question 1157218: log2(x + 1) + log2(x + 2) = log2 6
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+log%28+2%2C+x%2B1+%29+%2B+log%28+2%2C+x%2B2+%29+=+log%28+2%2C+6+%29+
+log%28+2%2C+%28x%2B1+%29%2A%28x%2B2%29+%29+=+log%28+2%2C6+%29+
+%28+x%2B1+%29%2A%28+x%2B2+%29+=+6+
+x%5E2+%2B+3x+%2B+2+=+6+
+x%5E2+%2B+3x+-+4+=+0+
complete the square
+x%5E2+%2B+3x+%2B+%28+3%2F2+%29%5E2+=+%28+3%2F2+%29%5E2+%2B+4+
+x%5E2+%2B+3x+%2B+9%2F4+=+9%2F4+%2B+16%2F4+
+%28+x+%2B+%283%2F2%29+%29%5E2+=+25%2F4+
+%28+x+%2B+%283%2F2%29+%29%5E2+=+%28+5%2F2+%29%5E2+
+x+%2B+3%2F2+=+5%2F2+
+x+=+1+
and
+x+%2B+3%2F2+=+-5%2F2+
+x+=+-4+
----------------------
check answers:
+log%28+2%2C+x%2B1+%29+%2B+log%28+2%2C+x%2B2+%29+=+log%28+2%2C+6+%29+
+log%28+2%2C+1%2B1+%29+%2B+log%28+2%2C+1%2B2+%29+=+log%28+2%2C+6+%29+
+log%28+2%2C2+%29+%2B+log%28+2%2C3+%29+=+log%28+2%2C6+%29+
+log%28+2%2C+2%2A3+%29+=+log%28+2%2C6+%29+
+log%28+2%2C6+%29+=+log%28+2%2C6+%29+
OK
I can't use the negative solution: that says that
2 raised to some power gives a negative result-
not valid.
get a 2nd opinion if needed