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.
107 exam-style questions on WJEC A Level Maths 3.1.1 Proof (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.