How to find the value of a?

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1 Answer
Mar 8, 2018

Answer:

#a = e#

Explanation:

Given the line

# y = m x#

and the curve

#y =ln x#

The tangency conditions are

#{(y = ln x),(y=mx),(y'=1/x),(y'=m):}#

hence

#{(lnx=1),(x=e):}#

determines the tangency point and consequently

#y = x/e# is the tangent line to #y = ln x# at point #x = e#