if tan theta equals x then prove that sin 2theta + tan 2theta = 4x/1 - x^4 please quick answer
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Answered by
17
Hi,
Here I am taking A instead of theta ,
tan A = x ---- ( 1 )
according to Phythagoruas Theorem ,
sin A = x / √( 1 + x² ) ---- ( 2 )
cosA = 1 / √( 1 + x² ) -----( 3 )
sin2A = 2sinAcosA
= 2 × [ x / √(1 + x² )] × [ 1 / √( 1 + x² )
{ since from ( 2 ) and ( 3 ) }
= 2x / ( 1 + x² ) -----( 4 )
tan2A = 2tanA / ( 1 - tan² A )
= 2x / ( 1 - x² ) { from ( 1 ) }
Therefore ,
sin 2A + tan2A
= 2x / ( 1 + x² ) + 2x / ( 1 - x² )
= 2x { ( 1 - x² + 1 + x² ) / [ ( 1 + x² ) ( 1 - x² ) ] }
= 2x { 2 / [ 1² - ( x² )² ] }
= 4x / ( 1 - x⁴ )
Hence proved ,
.
I hope this helps you.
:)
Here I am taking A instead of theta ,
tan A = x ---- ( 1 )
according to Phythagoruas Theorem ,
sin A = x / √( 1 + x² ) ---- ( 2 )
cosA = 1 / √( 1 + x² ) -----( 3 )
sin2A = 2sinAcosA
= 2 × [ x / √(1 + x² )] × [ 1 / √( 1 + x² )
{ since from ( 2 ) and ( 3 ) }
= 2x / ( 1 + x² ) -----( 4 )
tan2A = 2tanA / ( 1 - tan² A )
= 2x / ( 1 - x² ) { from ( 1 ) }
Therefore ,
sin 2A + tan2A
= 2x / ( 1 + x² ) + 2x / ( 1 - x² )
= 2x { ( 1 - x² + 1 + x² ) / [ ( 1 + x² ) ( 1 - x² ) ] }
= 2x { 2 / [ 1² - ( x² )² ] }
= 4x / ( 1 - x⁴ )
Hence proved ,
.
I hope this helps you.
:)
Answered by
0
Answer:
4x/1-x⁴
Step-by-step explanation:
The explanation is given above . Your welcome
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