Given that aaa, bbb, d d\,d and e e\,e are integers, where b≠0 b \ne 0\,b=0 and e≠0e \ne 0e=0, show that
de−ab \frac{d}{e}-\frac{a}{b} ed−bais rational.
Hence prove by contradiction that the sum of a rational number and an irrational number is irrational
368 exam-style questions on Edexcel A Level Maths Algebraic Methods, covering 1.1 Proof by Contradiction, 1.2 Algebraic Fractions, 1.3 Partial Fractions, 1.4 Repeated Factors, and 1.5 Algebraic Division. Each one has a worked solution and a mark scheme showing where the marks go.