Given that nnn is a positive integer, express
52+3n−53n−2 \frac{5}{2+3\sqrt{n}} - \frac{5}{3\sqrt{n}-2} 2+3n5−3n−25as a single fraction not involving surds.
Hence, deduce that
52+3n−53n−2 \frac{5}{2+3\sqrt{n}} - \frac{5}{3\sqrt{n}-2} 2+3n5−3n−25is a rational number for all positive integer values of nnn.
Practise Edexcel A Level Maths Algebraic Methods with exam-style questions for A Level Maths. 226 questions covering 1.1 Proof by Contradiction, 1.2 Algebraic Fractions, 1.3 Partial Fractions, 1.4 Repeated Factors, and 1.5 Algebraic Division, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.