It is given that a=2i+3j\mathbf{a} = 2\mathbf{i} + 3\mathbf{j}a=2i+3j and b=λi−4j\mathbf{b} = \lambda\mathbf{i} - 4\mathbf{j}b=λi−4j where λ \lambda\,λ is a constant.
Given that ∣a+b∣=5|\mathbf{a} + \mathbf{b}| = 5∣a+b∣=5, find the exact values of λ\lambdaλ.
168 exam-style questions on OCR (MEI) A Level Maths 1.11 Vectors, covering 1.11.1 Language of vectors in two dimensions, 1.11.2 Add, subtract and scale vectors, 1.11.3 Magnitude and direction of a vector, 1.11.4 Position vectors, 1.11.5 Distance between points by position vectors, 1.11.6 Vectors to solve problems, 1.11.7 Language of vectors in three dimensions (A-level only), and 1.11 Vectors. Each one has a worked solution and a mark scheme showing where the marks go.