0 mehakNewbie Asked: June 24, 20232023-06-24T20:33:40+05:30 2023-06-24T20:33:40+05:30In: CBSE 4. If sin A = 9/41, compute cos A and tan A. 0 Explain the question. Which formula is used? Class 10th, Rd sharma Trigonometric identies class 10th cbserd shrama trigonometric identities Share Facebook 1 Answer Voted Oldest Recent mehak Newbie 2023-06-25T19:49:11+05:30Added an answer on June 25, 2023 at 7:49 pm Solution: Given that, sin A = 9/41 …………. (1) Required to find: cos A, tan A By definition, we know that sin A = Perpendicular/ Hypotenuse……………(2) On Comparing eq. (1) and (2), we get Perpendicular side = 9 and Hypotenuse = 41 Let’s construct △ABC as shown below, And, here the length of base AB is unknown. Thus, by using Pythagoras theorem in △ABC, we get AC2 = AB2 + BC2 412 = AB2 + 92 AB2 = 412 – 92 AB2 = 168 – 81 AB= 1600 AB = √1600 AB = 40 ⇒ Base of triangle ABC, AB = 40 We know that, cos A = Base/ Hypotenuse cos A =AB/AC cos A =40/41 And, tan A = Perpendicular/ Base tan A = BC/AB tan A = 9/40 0 Reply Share Share Share on Facebook Share on Twitter Share on LinkedIn Share on WhatsApp Leave an answerLeave an answerCancel reply Featured image Select file Browse Add a Video to describe the problem better. Video type Youtube Vimeo Dailymotion Facebook Choose from here the video type. Video ID Put Video ID here: https://www.youtube.com/watch?v=sdUUx5FdySs Ex: "sdUUx5FdySs". Click on image to update the captcha. Visual Text Save my name, email, and website in this browser for the next time I comment. Related Questions Understanding the Curriculum Options at Boarding Schools in Dehradun 30. A well of diameter 2 m is dug 14 m deep. The earth taken out of it ... 29. A 16 m deep well with diameter 3.5 m is dug up, and the earth from it ... 28. A path 2 m wide surrounds a circular pond of diameter 40 m. How many cubic meters ... 27. A spherical ball of radius 3 cm is melted and recast into three spherical balls. The radii ...
Solution:
Given that, sin A = 9/41 …………. (1)
Required to find: cos A, tan A
By definition, we know that
sin A = Perpendicular/ Hypotenuse……………(2)
On Comparing eq. (1) and (2), we get
Perpendicular side = 9 and Hypotenuse = 41
Let’s construct △ABC as shown below,
And, here the length of base AB is unknown.
Thus, by using Pythagoras theorem in △ABC, we get
AC2 = AB2 + BC2
412 = AB2 + 92
AB2 = 412 – 92
AB2 = 168 – 81
AB= 1600
AB = √1600
AB = 40
⇒ Base of triangle ABC, AB = 40
We know that,
cos A = Base/ Hypotenuse
cos A =AB/AC
cos A =40/41
And,
tan A = Perpendicular/ Base
tan A = BC/AB
tan A = 9/40