Advertisements
Advertisements
प्रश्न
sec 60° = ?
विकल्प
`1/2`
2
`2/sqrt(3)`
`sqrt(3)`
`sqrt(2)`
Advertisements
उत्तर
2
Explanation:
`sec θ = 1/(cos θ)`
Since `cos 60^circ = 1/2`
`sec 60^circ = 1 ÷ (1/2)`
= 2
APPEARS IN
संबंधित प्रश्न
(1 + tan θ + sec θ) (1 + cot θ − cosec θ) = ______.
Prove the following trigonometric identities.
`cos A/(1 - tan A) + sin A/(1 - cot A) = sin A + cos A`
Prove the following identities:
`(cot^2 theta (sec theta - 1))/((1 + sin theta)) + (sec^2 theta(sin theta - 1))/((1 + sec theta)) = 0`
Write the value of cos1° cos 2°........cos180° .
Find the value of sin ` 48° sec 42° + cos 48° cosec 42°`
What is the value of (1 + cot2 θ) sin2 θ?
\[\frac{x^2 - 1}{2x}\] is equal to
cos4 A − sin4 A is equal to ______.
If sinA + cosA = m and secA + cosecA = n , prove that n(m2 - 1) = 2m
Verify that the points A(–2, 2), B(2, 2) and C(2, 7) are the vertices of a right-angled triangle.
Prove that `(sec θ - 1)/(sec θ + 1) = ((sin θ)/(1 + cos θ ))^2`
Proved that cosec2(90° - θ) - tan2 θ = cos2(90° - θ) + cos2 θ.
If `sqrt(3)` sin θ – cos θ = θ, then show that tan 3θ = `(3tan theta - tan^3 theta)/(1 - 3 tan^2 theta)`
sin2θ + sin2(90 – θ) = ?
Given that sinθ + 2cosθ = 1, then prove that 2sinθ – cosθ = 2.
If cosA + cos2A = 1, then sin2A + sin4A = 1.
Simplify (1 + tan2θ)(1 – sinθ)(1 + sinθ)
Show that: `tan "A"/(1 + tan^2 "A")^2 + cot "A"/(1 + cot^2 "A")^2 = sin"A" xx cos"A"`
Prove the following that:
`tan^3θ/(1 + tan^2θ) + cot^3θ/(1 + cot^2θ)` = secθ cosecθ – 2 sinθ cosθ
Find the value of sin2θ + cos2θ
Solution:
In Δ ABC, ∠ABC = 90°, ∠C = θ°
AB2 + BC2 = `square` .....(Pythagoras theorem)
Divide both sides by AC2
`"AB"^2/"AC"^2 + "BC"^2/"AC"^2 = "AC"^2/"AC"^2`
∴ `("AB"^2/"AC"^2) + ("BC"^2/"AC"^2) = 1`
But `"AB"/"AC" = square and "BC"/"AC" = square`
∴ `sin^2 theta + cos^2 theta = square`
