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Prove that `1/("cosec" theta - cot theta)` = cosec θ + cot θ
Concept: Trigonometric Identities (Square Relations)
If cos(45° + x) = sin 30°, then x = ?
Concept: Trigonometric Ratios in Terms of Coordinates of Point
If tan θ = `7/24`, then to find value of cos θ complete the activity given below.
Activity:
sec2θ = 1 + `square` ......[Fundamental tri. identity]
sec2θ = 1 + `square^2`
sec2θ = 1 + `square/576`
sec2θ = `square/576`
sec θ = `square`
cos θ = `square` .......`[cos theta = 1/sectheta]`
Concept: Trigonometric Identities (Square Relations)
Prove that `sec"A"/(tan "A" + cot "A")` = sin A
Concept: Trigonometric Identities (Square Relations)
Prove that `"cot A"/(1 - tan "A") + "tan A"/(1 - cot"A")` = 1 + tan A + cot A = sec A . cosec A + 1
Concept: Trigonometric Identities (Square Relations)
The value of 2tan45° – 2sin30° is ______.
Concept: Trigonometric Table
Complete the following activity to prove:
cotθ + tanθ = cosecθ × secθ
Activity: L.H.S. = cotθ + tanθ
= `cosθ/sinθ + square/cosθ`
= `(square + sin^2theta)/(sinθ xx cosθ)`
= `1/(sinθ xx cosθ)` ....... ∵ `square`
= `1/sinθ xx 1/cosθ`
= `square xx secθ`
∴ L.H.S. = R.H.S.
Concept: Trigonometric Identities (Square Relations)
If sinθ = `11/61`, then find the value of cosθ using the trigonometric identity.
Concept: Trigonometric Identities (Square Relations)
Show that: `tan "A"/(1 + tan^2 "A")^2 + cot "A"/(1 + cot^2 "A")^2 = sin"A" xx cos"A"`
Concept: Trigonometric Identities (Square Relations)
In ΔABC, ∠ABC = 90° and ∠ACB = θ. Then write the ratios of sin θ and tan θ from the figure.

Concept: Trigonometric Ratios
Prove that sec θ + tan θ = `cos θ/(1 - sin θ)`.
Proof: L.H.S. = sec θ + tan θ
= `1/square + square/square`
= `square/square` ......`(∵ sec θ = 1/square, tan θ = square/square)`
= `((1 + sin θ) square)/(cos θ square)` ......[Multiplying `square` with the numerator and denominator]
= `(1^2 - square)/(cos θ square)`
= `square/(cos θ square)`
= `cos θ/(1 - sin θ)` = R.H.S.
∴ L.H.S. = R.H.S.
∴ sec θ + tan θ = `cos θ/(1 - sin θ)`
Concept: Trigonometric Ratios
Find the value of sin 0° + cos 0° + tan 0° + sec 0°.
Concept: Trigonometric Ratios
Find the value of sin 45° + cos 45° + tan 45°.
Concept: Trigonometric Ratios
Prove that: (sec θ – cos θ) (cot θ + tan θ) = tan θ.sec θ
Proof: L.H.S. = (sec θ – cos θ) (cot θ + tan θ)
= `(1/square - cos θ) (square/square + square/square)` ......`[∵ sec θ = 1/square, cot θ = square/square and tan θ = square/square]`
= `((1 - square)/square) ((square + square)/(square square))`
= `square/square xx 1/(square square)` ......`[(∵ square + square = 1),(∴ square = 1 - square)]`
= `square/(square square)`
= tan θ.sec θ
= R.H.S.
∴ L.H.S. = R.H.S.
∴ (sec θ – cos θ) (cot θ + tan θ) = tan θ.sec θ
Concept: Angles of Elevation and Depression
What will be the value of sin 45° + `1/sqrt(2)`?
Concept: Trigonometric Ratios
In the given figure, if sin θ = `7/13`, which angle will be θ?

Concept: Trigonometric Ratios
Prove that: cot θ + tan θ = cosec θ·sec θ
Proof: L.H.S. = cot θ + tan θ
= `square/square + square/square` ......`[∵ cot θ = square/square, tan θ = square/square]`
= `(square + square)/(square xx square)` .....`[∵ square + square = 1]`
= `1/(square xx square)`
= `1/square xx 1/square`
= cosec θ·sec θ ......`[∵ "cosec" θ = 1/square, sec θ = 1/square]`
= R.H.S.
∴ L.H.S. = R.H.S.
∴ cot θ + tan θ = cosec·sec θ
Concept: Trigonometric Ratios
If sec θ = `1/2`, what will be the value of cos θ?
Concept: Trigonometric Ratios
Find will be the value of cos 90° + sin 90°.
Concept: Trigonometric Ratios
If cot θ = `40/9`, find the values of cosec θ and sinθ,
We have, 1 + cot2θ = cosec2θ
1 + `square` = cosec2θ
1 + `square` = cosec2θ
`(square + square)/square` = cosec2θ
`square/square` = cosec2θ ......[Taking root on the both side]
cosec θ = `41/9`
and sin θ = `1/("cosec" θ)`
sin θ = `1/square`
∴ sin θ = `9/41`
The value is cosec θ = `41/9`, and sin θ = `9/41`
Concept: Trigonometric Identities (Square Relations)
