A curve has the equation y=ekxy = e^{kx}y=ekx, where k>0k>0k>0
Find, in terms of a a\,a and kkk, the equation of the tangent to the curve at the point (a,eka)(a, e^{ka})(a,eka)
Find the value of a a\,a for which this tangent passes through the origin.
Hence, find the set of values of m m\,m for which the equation ekx=mxe^{kx} = mxekx=mx has no real solutions.
277 exam-style questions on Edexcel A Level Maths Exponentials and Logarithms, covering 14.1 Exponential Functions, 14.2 y = e^x, 14.3 Exponential Modelling, 14.4 Logarithms, 14.5 Laws of Logarithms, 14.6 Solving Equations using Logarithms, 14.7 Working with Natural Logarithms, and 14.8 Logarithms and Non-Linear Data. Each one has a worked solution and a mark scheme showing where the marks go.