Ex 8.1, 1
In Δ ABC, right-angled at B, AB = 24 cm, BC = 7 cm. Determine :
sin A, cos A
Step1 : Finding sides of triangle
In right triangle ABC,
using Pythagoras theorem
(Hypotenuse)2 = (Height)2 + (Base)2
AC2 = AB2 + BC2
= 242 + 72
= 24×24×7×7
= 576 + 49
AC2 = 625
AC = √625
= √(25×25) =√(〖25〗^2 ) = 25
Hence AC = 25 cm
Step 2: Finding sin A , cos A
Ex 8.1 ,1
In Δ ABC, right-angled at B, AB = 24 cm, BC = 7 cm. Determine :
(ii) sin C, cos C
Now,
AC = 25 cm , AB = 24 cm , BC = 7 cm
sin C = (𝑠𝑖𝑑𝑒 𝑜𝑝𝑝𝑜𝑠𝑖𝑡𝑒 𝑡𝑜 ∠ 𝐶)/𝐻𝑦𝑝𝑜𝑡𝑒𝑛𝑢𝑠𝑒
= 𝐴𝐵/𝐴𝐶
= 24/25

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.

Hi, it looks like you're using AdBlock :(

Displaying ads are our only source of revenue. To help Teachoo create more content, and view the ad-free version of Teachooo... please purchase Teachoo Black subscription.

Please login to view more pages. It's free :)

Teachoo gives you a better experience when you're logged in. Please login :)

Solve all your doubts with Teachoo Black!

Teachoo answers all your questions if you are a Black user!