If secθ - tanθ = p, then secθ is equal to:
If secθ - tanθ = p, then secθ is equal to: Correct Answer p/2 + 1/(2p)
Given that:
secθ - tanθ = p
Quantity used:
1 + tan2θ = sec2θ
calculation:
⇒ secθ - tanθ = p ------(1)
multiply and divide equation (1) by (secθ + tanθ)
⇒ (secθ - tanθ)(secθ + tanθ)/(secθ + tanθ) = p
⇒ (sec2θ + secθtanθ - secθtanθ - tan2θ)/(secθ + tanθ) = p
⇒ (sec2θ - tan2θ)/(secθ + tanθ) = p
∵ sec2θ - tan2θ = 1
∴ 1/(secθ + tanθ) = p
⇒ secθ + tanθ = 1/p ------(2)
Add equation(1) and (2)
⇒ secθ - tanθ + secθ - tanθ = p + 1/p
⇒ 2secθ = p + 1/p
∴ secθ = p/2 + 1/(2p)
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Feb 20, 2025