# Math (Calculus)

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Can somebody solve this logarithm problem step by step for me please:

2(lnx)² + lnx-1 = 0

First let y = ln x be a new variable, , and solve the polynomial
2 y^2 + y - 1 = 0
2(y +1)(y - 1/2) = 0
Solutions are
y = -1 or +1/2
Thus x = e^y
and x= 1/e = 0.3679.. OR
e^0.5 = 1.6487..

• Math (Calculus) -

tg(x)sec^6(x)dx

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