I keep trying this problem over and over again, and I can't get the answer that's in the back of the book. Can someone tell me where I'm going wrong?
0.3 ^(1+x) = 1.7 ^ (2x-1)
(1+x) ln 0.3 = (2x-1) ln 1.7
ln 0.3 + x ln .3 = 2x ln 1.7 - ln 1.7
x ln 0.3 - 2x ln 1.7 = -ln 1.7 - ln .3
x(ln 0.3 - 2ln 1.7) = -ln 1.7 - ln .3
x= (-ln 1.7 - ln .03) / (ln 0.3 - 2ln 1.7)
In the back of the book the answer is (ln .51) / (ln 9.63)
help?? what am i doing wrong?
0.3 ^(1+x) = 1.7 ^ (2x-1)
(1+x) ln 0.3 = (2x-1) ln 1.7
ln 0.3 + x ln .3 = 2x ln 1.7 - ln 1.7
x ln 0.3 - 2x ln 1.7 = -ln 1.7 - ln .3
x(ln 0.3 - 2ln 1.7) = -ln 1.7 - ln .3
x= (-ln 1.7 - ln .03) / (ln 0.3 - 2ln 1.7)
In the back of the book the answer is (ln .51) / (ln 9.63)
help?? what am i doing wrong?
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Actually, there is one little thing
-ln(.03) is supposed to be -ln(.3)
Other than that, all you need is a little simplification
-ln1.7 - ln.3 = -(ln1.7+ln.3)
-ln1.7 - ln.3 = -(ln(1.7*.3)) = -ln(.51)
ln(.3) - 2ln(1.7) = -(ln(.3) - ln(2.89))
-ln(2.89/.3)= -ln(9.63)
Apply these values and you get:
-ln(.51)/-ln(9.63)
Which equals to:
ln(.51)/ln(9.63)
Hope this helped!
-ln(.03) is supposed to be -ln(.3)
Other than that, all you need is a little simplification
-ln1.7 - ln.3 = -(ln1.7+ln.3)
-ln1.7 - ln.3 = -(ln(1.7*.3)) = -ln(.51)
ln(.3) - 2ln(1.7) = -(ln(.3) - ln(2.89))
-ln(2.89/.3)= -ln(9.63)
Apply these values and you get:
-ln(.51)/-ln(9.63)
Which equals to:
ln(.51)/ln(9.63)
Hope this helped!
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It should be easy by taking logarithm both sides. Then:
log 0.3^(1+x) = log 1.7 ^( 2x-1)
or,(1+x) log.3 = (2x-1) log 1.7
or,(1+x)*-0.52 =(2x-1)*.23
or, -.52 -.52x = .46x - .23
or, -0.29 - .98x = 0
or, x = -0.29/.98 = - 0.29
or, x= - 0.29 is the answer.
log 0.3^(1+x) = log 1.7 ^( 2x-1)
or,(1+x) log.3 = (2x-1) log 1.7
or,(1+x)*-0.52 =(2x-1)*.23
or, -.52 -.52x = .46x - .23
or, -0.29 - .98x = 0
or, x = -0.29/.98 = - 0.29
or, x= - 0.29 is the answer.