The intensity levels of a signal at three consecutive nodes in a fiber-optic circuit are recorded as k units, (2k+3) units, and (2k+14) unitsk \text{ units}, \, (2k + 3) \text{ units}, \text{ and } (2k + 14) \text{ units}k units,(2k+3) units, and (2k+14) units, where kkk is a real constant.
Use proof by contradiction to show that these intensity levels cannot form a geometric sequence.
132 exam-style questions on OCR (MEI) A Level Maths 1.1 Proof, covering 1.1.1 Structure of mathematical proof, 1.1.2 Disproof by counter example, 1.1.3 Proof by contradiction (A-level only), and 1.1 Proof. Each one has a worked solution and a mark scheme showing where the marks go.