What is the simplified value of \(\frac{1-\cos^2 x}{\sin^2 x}\)?
Answer and explanation
Correct answer: \(1\)
Using the Pythagorean identity \(\sin^2 x+\cos^2 x=1\), we get \(1-\cos^2 x=\sin^2 x\). Therefore, \(\frac{1-\cos^2 x}{\sin^2 x}=\frac{\sin^2 x}{\sin^2 x}=1\), provided \(\sin x\ne 0\). Neither \(\sin x\), \(\cos x\), nor \(\tan x\) is the simplified value of this ratio. Exam tip: first replace \(1-\cos^2 x\) with \(\sin^2 x\) in such questions.
Frequently asked questions
What is the correct answer to this question?
\(1\)
Why is this the correct answer?
Using the Pythagorean identity \(\sin^2 x+\cos^2 x=1\), we get \(1-\cos^2 x=\sin^2 x\). Therefore, \(\frac{1-\cos^2 x}{\sin^2 x}=\frac{\sin^2 x}{\sin^2 x}=1\), provided \(\sin x\ne 0\). Neither \(\sin x\), \(\cos x\), nor \(\tan x\) is the simplified value of this ratio. Exam tip: first replace \(1-\cos^2 x\) with \(\sin^2 x\) in such questions.
Which subject and chapter does this question cover?
This is a Class 12 Mathematics question. Chapter: Trigonometric Functions. Topic: Trigonometric functions and their properties.