16 дек. 2015 г. · FYI: Here's a trigonograph (picture proof), where you would take x=A+B and y=A−B (so that A=(x+y)/2 and B=(x−y)/2). Proving $|\sin x - \sin y| < |x - y - Math Stack Exchange Why does $\sin(x) - \sin(y)=2 \cos(\frac{x+y}{2}) \sin(\frac{x-y}{2}) Другие результаты с сайта math.stackexchange.com

Продолжительность: 4:19
Опубликовано: 3 дек. 2018 г.

21 авг. 2015 г. · Draw unit circle with center O and mark off radial lines OA, OX, OY at angles of 0, x and y radians. Draw vertical lines XX' and YY' meeting OA at X' and Y'. How to derive the formula [math]\sin (x+y) = \sin(x)\cos ... What is a proof for sin (x + y) = sin x *cos y + cos x *sin y? If sin x = -sin y, what are the possible values of x and y? How do you prove that sin(x) sin(y) = (1/2) [cos (x - y) Другие результаты с сайта www.quora.com

Продолжительность: 2:10
Опубликовано: 14 авг. 2020 г.

9 янв. 2020 г. · If sin(y+z−x),sin(z+x−y),sin(x+y−z) be in A.P., prove that tanx,tany,tanz are also in A.P..

Продолжительность: 5:08
Опубликовано: 25 июл. 2022 г.

Prove that sin(x)+sin(y)=2sin((x+y)/2)cos((x-y)/2) · Need help with Maths? · Download MyTutor's free revision handbook? · Free weekly group tutorials.

22 мая 2015 г. · Apply the Mean Value Theorem to the function f(z)=sin(z) on the closed interval [x,y], which can be done because f is definitely continuous and differentiable ...

23 февр. 2023 г. · Theorem 1 For any real numbers x and y, sinx=siny implies x=nπ+(−1)ny, where n∈Z Proof If sinx=siny, then sinx−siny=0 or 2cos2x+y​sin2x=y​=0 ...