KnowledgeBoat Logo

Mathematics

If cosec θ = 1312\dfrac{13}{12}, then the value of tan θ is

  1. 125\dfrac{12}{5}

  2. 512\dfrac{5}{12}

  3. 513\dfrac{5}{13}

  4. 512\dfrac{5}{12}

Trigonometrical Ratios

5 Likes

Answer

Let ABC be a right angle triangle with ∠B = 90° and ∠C = θ.

If cosec θ = 13/12, then the value of tan θ is? Trigonometrical Ratios, ML Aggarwal Understanding Mathematics Solutions ICSE Class 9.

By formula,

cosec θ = HypotenusePerpendicular\dfrac{\text{Hypotenuse}}{\text{Perpendicular}}

Substituting values we get :

1312=ACAB\Rightarrow \dfrac{13}{12} = \dfrac{AC}{AB}

Let AC = 13x and AB = 12x.

In right angle triangle ABC,

⇒ AC2 = AB2 + BC2

⇒ (13x)2 = (12x)2 + BC2

⇒ 169x2 = 144x2 + BC2

⇒ BC2 = 169x2 - 144x2

⇒ BC2 = 25x2

⇒ BC = 25x2=5x\sqrt{25x^2} = 5x.

By formula,

tan θ = PerpendicularBase=ABBC=12x5x=125\dfrac{\text{Perpendicular}}{\text{Base}} = \dfrac{AB}{BC} = \dfrac{12x}{5x} = \dfrac{12}{5}.

Hence, Option 1 is the correct option.

Answered By

3 Likes


Related Questions