If secθ + tanθ = p. find the value of cosecθ.
Answers
Refer to the attachment^^ ♥️❤️
cosec∅ = (p²+1)/(p²-1)
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Given : sec∅ + tan∅ = p
To find : cosec∅
Solution : We know that,
Sec²∅ - tan²∅ = 1 [ trigonometry identity ]
Also, a² - b² = (a+b)(a-b)
So, (sec∅+tan∅)(sec∅-tan∅) = 1 ...(i)
It is given that, (sec∅ + tan∅ = p)
Now, put (sec∅ + tan∅ = p) in eq (i)
We get,
p(sec∅-tan∅) = 1
sec∅ - tan∅ = 1/p ....(ii)
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Adding (i) and (ii),
We get,
2sec∅ = p+1/p
=> sec∅ = p²+1/2p
Now, cosθ=1/secθ=2p/(p²+1)
Therefore, sin∅=√(1-cos²∅)
=>√[1-{2p/(p²+1)}²] =√[1-4p²/(p²+1)²]
=>√[{(p²+1)²-4p²}/(p²+1)²]
=>√[(p⁴+2p²+1-4p²)/(p²+1)²]
=>√(p⁴-2p²+1)/(p²+1)
=>√(p²-1)²/(p²+1)
=> (p²-1)/(p²+1)
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Also, cosec∅ = 1/sin∅
=> 1/[(p²-1)/(p²+1)]
After reciprocal,
We get,
=> (p²+1)/(p²-1)
Hence, cosec∅ = (p²+1)/(p²-1)