NCERT · Class 10 · Mathematics · Introduction to TrigonometryThe value of $\sec A (1 - \sin A)(\sec A + \tan A)$ is:
Simplify the expression by writing $\sec A = \frac{1}{\cos A}$ and $\tan A = \frac{\sin A}{\cos A}$. The expression becomes $\frac{1}{\cos A}(1 - \sin A)(\frac{1 + \sin A}{\cos A}) = \frac{(1 - \sin A)(1 + \sin A)}{\cos^2 A} = \frac{1 - \sin^2 A}{\cos^2 A}$. Since $1 - \sin^2 A = \cos^2 A$, we get $\frac{\cos^2 A}{\cos^2 A} = 1$.
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Introduction to Trigonometry.
Correct choice. Refer to the step-by-step verified solution guidelines above for details.
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Introduction to Trigonometry.
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Introduction to Trigonometry.