In a digital communications system, the power levels of discrete signals are modeled by the function P(k)=k2−10P(k) = k^2 - 10P(k)=k2−10, where kkk is an integer representing the signal index. Use the method of proof by contradiction to prove that it is impossible for any signal power P(k)P(k)P(k) to be exactly divisible by 4.
Practise Edexcel A Level Maths 1.1 Proof by Contradiction with exam-style questions for A Level Maths. 100 questions, 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.