Question

plz solve this problem​

Answer 1

Step-by-step explanation:

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Answer 2

Step-by-step explanation:

$\sf ( 1 + {tan}^{2}\theta )( 1 - sin\theta )( 1 + sin\theta) \\ \\ \sf = ( 1 + {tan}^{2}\theta )( 1 - {sin}^{2}\theta ) \\ \\ \sf = {sec}^{2}\theta × {cos}^{2}\theta \\ \\ \sf = {cos}^{2}\theta × \frac{1}{{cos}^{2}\theta } \\ \\ \sf = 1 \\ \\ \sf Identities\: used \\ \\ \sf \star {sin}^{2}\theta + {cos}^{2}\theta = 1 \\ \\ \sf \star 1 + {tan}^{2}\theta = {sec}^{2}\theta \\ \\ \sf \star sec\theta = \frac{1}{cos\theta} \\ \\ \sf \star ( a + b )( a - b ) = {a}^{2} - {b}^{2}$