Teaching Railway Teacher PRT 2025 Mock Test Series Quantitative Aptitude Trigonometry Trigonometric Ratios and Identities
\(\text{If } \cos^4 \theta - \sin^4 \theta = k, \text{ then the value of } \frac{1-k}{1+k} \text{ is:}\)
1
tan²θ
2
sin²θ
3
cot²θ
4
cosec²θ