SOLUTION: Log[2x^2+5x-2]=1

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Question 1120816: Log[2x^2+5x-2]=1
Found 2 solutions by ankor@dixie-net.com, MathLover1:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Log[2x^2+5x-2]=1
log(10) = 1
therefore
2x^2 + 5x -2 = 10
2x^2 + 5x - 2 - 10 = 0
2x^2 + 5x - 12 = 0
Factors to
(2x-3)(x+4) = 0
two solutions
2x = 3
x = 1.5
and
x = -4
:
Check both solutions in the original equation

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

log%282x%5E2%2B5x-2%29=1+....recall log%2810%29=1
log%282x%5E2%2B5x-2%29=log%2810%29+
+2x%5E2%2B5x-2=10
2x%5E2%2B5x-2-10=0
2x%5E2%2B5x-12=0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-5+%2B-+sqrt%28+5%5E2-4%2A2%2A%28-12%29+%29%29%2F%282%2A2%29+
x+=+%28-5+%2B-+sqrt%28+25%2B96+%29%29%2F4+
x+=+%28-5+%2B-+sqrt%28121+%29%29%2F4+
x+=+%28-5+%2B-+11%29%2F4+
solutions:
x+=+%28-5+%2B+11%29%2F4+
x+=+6%2F4+
highlight%28x+=+3%2F2%29+

x+=+%28-5-+11%29%2F4+
x+=+%28-+16%29%2F4+
highlight%28x+=+-+4%29+