sec theta+tan theta=p find the value of cosec theta
Answers
Step-by-step explanation:
Secθ+tanθ=p ----------------------(1)
∵, sec²θ-tan²θ=1
or, (secθ+tanθ)(secθ-tanθ)=1
or, secθ-tanθ=1/p ----------------(2)
Adding (1) and (2) we get,
2secθ=p+1/p
or, secθ=(p²+1)/2p
∴, cosθ=1/secθ=2p/(p²+1)
∴, sinθ=√(1-cos²θ)
=√[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)
So ,cosecθ=1/sinθ=1/[(p²-1)/(p²+1)]=(p²+1)/(p²-1)
Answer:
Given :
sec A + tan A = p
I am replacing p by ' k '
sec A + tan A = k
We know :
sec A = H / B & tan A = P / B
H / B + P / B = k / 1
H + P / B = k / 1
So , B = 1
H + P = k
P = k - H
From pythagoras theorem :
H² = P² + B²
H² = ( H - k )² + 1
H² = H² + k² - 2 H k + 1
2 H k = k² + 1
H = k² + 1 / 2 k
P = k - H
P = k² - 1 / 2 k
Now write k = p we have :
Base = 1
Perpendicular P = P² - 1 / 2 P
Hypotenuse H = P² + 1 / 2 P
Value of cosec A = H / P
cosec A = P² + 1 / 2 P / P² - 1 / 2 P
cosec A = P² + 1 / P² - 1