alleryStart learning →The fundamental identity relating $\sin A$ and $\cos A$ is
A$\sin^2 A - \cos^2 A = 1$
B$\sin^2 A + \cos^2 A = 1$
C$\sin A + \cos A = 1$
D$\sin^2 A + \cos^2 A = 0$
Answer & Solution
Correct answer: B. $\sin^2 A + \cos^2 A = 1$
1. This identity follows from the Pythagoras theorem.
2. $\sin^2 A + \cos^2 A = 1$ for any angle A.
3. It is the most-used trigonometric identity.
_Source: Karnataka SSLC (KSEEB) Class 10 Mathematics, Ch11 'Introduction to Trigonometry', §11.4_
Keep practising Introduction to Trigonometry
Browse all Introduction to Trigonometry questions for Karnataka SSLC (Class 10), or explore more Mathematics topics.
Related questions