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प्रश्न
\[\frac{1 - \sin A}{\cos A} = \sec A - \tan A.\]
Statement (1): \[\frac{1 - \sin A}{\cos A} = \sec A - \tan A\]
\[\Rightarrow \frac{1 + \sin A}{\cos A} = \sec A + \tan A\]
Statement (2): \[\frac{1 - \sin A}{\cos A} - \frac{1 + \sin A}{\cos A} = 2\sec A\]
विकल्प
Both the statements are true.
Both the statements are false.
Statement 1 is true, and statement 2 is false.
Statement 1 is false, and statement 2 is true.
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उत्तर
Statement 1 is true, and statement 2 is false.
Explanation:
Given, \[\frac{1 - \sin A}{\cos A} = \sec A - \tan A\]
Taking L.H.S.
\[\Rightarrow \frac{1 - \sin A}{\cos A}\]
\[\Rightarrow \frac{1}{\cos A} - \frac{\sin A}{\cos A}\]
\[\Rightarrow \sec A - \tan A\]
As, L.H.S. = R.H.S., so equation is true.
Now, \[\frac{1 + \sin A}{\cos A} = \sec A + \tan A\]
Taking L.H.S.
\[\Rightarrow \frac{1 + \sin A}{\cos A}\]
\[\Rightarrow \frac{1}{\cos A} + \frac{\sin A}{\cos A}\]
\[\Rightarrow \sec A + \tan A\]
As, L.H.S. = R.H.S., so equation is true.
So, statement 1 is true.
Now, \[\frac{1 - \sin A}{\cos A} - \frac{1 + \sin A}{\cos A} = 2\sec A\]
Solving L.H.S.
\[\Rightarrow \frac{1 - \sin A}{\cos A} - \frac{1 + \sin A}{\cos A}\]
\[\Rightarrow \frac{1}{\cos A} - \frac{\sin A}{\cos A} - \left(\frac{1}{\cos A} + \frac{\sin A}{\cos A}\right)\]
⇒ (sec A − tan A) − (sec A + tan A)
⇒ sec A − tan A − sec A v tan A
⇒ −2tan A.
As, L.H.S. ≠ R.H.S.
So, statement 2 is false.
∴ Statement 1 is true and statement 2 is false.
