0 Deepak BoraNewbie Asked: July 10, 20202020-07-10T12:23:23+05:30 2020-07-10T12:23:23+05:30In: CBSE Trigonometric formula… Prove that : Sin² A=1-cos²A 0 Prove this standard trigonometric identity: Sin² A=1-cos²A cosidentitiessintrigonometric formulatrigonometry Share Facebook 1 Answer Voted Oldest Recent Deepak Bora Newbie 2020-07-15T13:01:00+05:30Added an answer on July 15, 2020 at 1:01 pm To prove:- Sin²A = 1-cos² A In a right triangle SinA = P/H CosA = B/H substituting the values (P/H)² = 1- (B/H)² P²/H² = 1- B²/H² P²/H² = H² – B²/H². (Taking LCM) According to P.G.T. H²= P²+ B² ∴H² – B² = P² ∴ P²/H² = P²/ H². RHS= LSH ( Hence Proved) -1 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. Save my name, email, and website in this browser for the next time I comment. Related Questions If tanθ=4/3, show that (sinθ+cosθ)=7/5 If cosec θ= 2 show that (cot θ + sin θ / 1 + cos θ) = 2 If 15cotA = 8, find the values of sin A and secA. If sin θ= √3/2, find the value of all T-ratios of θ A T.V. Tower stands vertically on a bank of a river. From a point on the other bank ...
To prove:- Sin²A = 1-cos² A
In a right triangle
SinA = P/H
CosA = B/H
substituting the values
(P/H)² = 1- (B/H)²
P²/H² = 1- B²/H²
P²/H² = H² – B²/H². (Taking LCM)
According to P.G.T. H²= P²+ B²
∴H² – B² = P²
∴ P²/H² = P²/ H².
RHS= LSH ( Hence Proved)