The sin(π/2-x) formula is given as follows: sin(π/2-x)=cosx …(∗) The formula of sin(pi/2-θ) is given by sin(π/2-θ)=cosθ. In this post, we will learn how to compute sin(pi/2-x) or sin(θ-pi/2). Proof of sin(pi/2-x) Formula To establish the above formula (∗), that is, the formula of sin(π/2-x), we need to apply the below formula: sin(a-b) = sina … Read more
For any x, sin(pi-x) formula is given below: sin(pi-x)=sinx Similarly, sin(pi-theta)=sin theta. In this post, we will learn how to compute sin(pi-x) or sin(pi-theta). sin(pi-x) Simplify To find the formula of sin(π-x), we will apply the following trigonometric identity: sin(A-B) = sinA cosB – cosA sinB …(∗) Here we put A=π and B=x; so that … Read more
The general solutions of sinx=-1 are given by x=(4n-1)π/2 where n is any integer. In this post, we will learn how to find the general solutions of the trigonometric equation sinx=-1. sinx=-1 General Solution Question: Find the general solutions of sinx= -1. Answer: As sin(-π/2)= -1, the equation sinx= -1 can be written sinx = … Read more
The general solution of sinx=1 is given by x=(4n+1)π/2 where n is any integer. In this post, we will learn how to find the general solutions of the trigonometric equation sinx=1. sinx=1 General Solution Question: Find the general solutions of sinx=1. Answer: As sin(π/2)=1, the equation sinx=1 can be written sinx = sin(π/2). ∴ x=mπ+(-1)m … Read more
The simplification or the formula of 1+cot2x is given as follows: 1+cot2x = cosec2x. In this post, we will learn how to establish the formula of 1+cot2x. Proof of 1+cot2x Formula Question: Prove the formula 1+cot2x = cosec2x. Solution: L.H.S. = 1+cot2x = $1+(\dfrac{\cos x}{\sin x})^2$ as cotx=cosx/sinx. = $1+\dfrac{\cos^2 x}{\sin^2 x}$ = $\dfrac{\sin^2 x … Read more
The cot(x+y) formula or the identity is given by cot(x+y) = $\dfrac{\cot x \cot y -1}{\cot x + \cot y}$. Here we will prove the formula of cot x+y. Proof of cot(x+y) Formula cot(x+y) = $\dfrac{\cot x \cot y -1}{\cot x + \cot y}$. Proof: Let us recall the following two formulas: sin(x+y) = sinx … Read more
The tan(x-y) is the tangent of the difference of the angles x and y. Tan(x-y) formula/identity is given as follows: tan(x-y) = $\dfrac{\tan x -\tan y}{1+\tan x \tan y}$. In this post, we will prove the formula of tan x-y. Proof of tan(x-y) Formula tan(x-y) = $\dfrac{\tan x -\tan y}{1+\tan x \tan y}$ Proof: We … Read more
The function cosx siny is the product of a cosine function and a sine function. In this post, we will learn how to prove the formula/identity of cosx siny. cosx siny Formula The cosx siny formula is given as follows: cosx siny = $\dfrac{\sin(x+y)-\sin(x-y)}{2}$ Let us now prove the above formula of cos x sin … Read more
The formula or the identity of the product sinx cosy is obtained by the transformation of sums or differences of trigonometric angles. sinx cosy formula is given below. sinx cosy = $\dfrac{\sin(x+y)+\sin(x-y)}{2}$ Proof of sinx cosy Formula Let us now prove the sinx siny formula sinx cosy = $\dfrac{\sin(x+y)+\sin(x-y)}{2}$ Proof: It is known that sin(x+y) … Read more
The function sinx siny is the product of two sine functions sinx and siny. The formula or the identity of sinx siny is given as follows: sinx siny = $\dfrac{\cos(x-y)-\cos(x+y)}{2}$ Proof of sinx siny Formula We will now prove the sinx siny formula sinx siny = $\dfrac{\cos(x-y)-\cos(x+y)}{2}$ Proof: We know that cos(x+y) = cosx cosy … Read more