2)
tan A 1+sec A
+
1 + sec A
tan A
is equal to
B) 2sec A
A) 2cosec A
C) 2sin A
D) 2cos A
Answers
Answered by
1
Step-by-step explanation:
(sinA+cscA)
2
+(cosA+secA)
2
=sin
2
A+csc
2
A+2sinAcscA+cos
2
A+sec
2
A+2cosAsecA .......As[a²+b²+2ab=(a+b)²]
=sin
2
A+csc
2
A+2sinA×
sinA
1
+cos
2
A+sec
2
A+2cosA
cosA
1
.
........... since secA=
cosA
1
and cscA=
sinA
1
=sin
2
A+csc
2
A+2+cos
2
A+sec
2
A+2
=(sin
2
A+cos
2
A)+csc
2
A+sec
2
A+4
=1+1+cot
2
A+1+tan
2
A+4 ........... since csc
2
A=1+cot
2
A and sec
2
A=1+tan
2
A
=7+tan
2
A+cot
2
A
Hence proved.
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