The intensity, III, of a specialized acoustic wave at a distance rrr from the source is modeled by the equation:
I=rsin(2r),r>0,I>0 I = r^{\sin(2r)}, \quad r > 0, \quad I > 0 I=rsin(2r),r>0,I>0By first taking natural logarithms, find an expression for dIdr\frac{dI}{dr}drdI in terms of III and rrr.
Hence show that at any stationary point of the intensity, the distance rrr must satisfy the equation:
tan(2r)+2rlnr=0 \tan(2r) + 2r \ln r = 0 tan(2r)+2rlnr=0263 exam-style questions on CCEA A Level Maths 3.5 Differentiation (A-level only), covering 3.5.1 Differentiation (A-level only), 3.5.2 Differentiation (A-level only), 3.5.3 Differentiation (A-level only), 3.5.4 Differentiation (A-level only), 3.5.5 Differentiation (A-level only), and 3.5 Differentiation (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.