Additional Mathematics 0606 / Series / 3.153.15: Logarithmic AP and GP sum to infinity0606/11/M/J/22 — Question 7 · 9 marksMark as done · Save for later · Show all solutions(a)The first three terms of an AP are lg3\lg3lg3, lg9\lg9lg9, lg27\lg27lg27. Given that Sn=256lg81S_{n}=256\lg81Sn=256lg81, find nnn.[5]▸ Answer(b)DO NOT USE A CALCULATOR.A GP has first three terms ln256\ln256ln256, ln16\ln16ln16, ln4\ln4ln4. Find S∞S_{\infty}S∞ in the form ln(2p)\ln(2^{p})ln(2p).[4]▸ Answer▸ Official mark scheme← 3.70: Binomial expansion coefficients3.67: Binomial expansion in descending powers →
