Showing posts with label Equation for Velocity. Show all posts
Showing posts with label Equation for Velocity. Show all posts

Monday, 16 July 2012

solving trigonometric equations

In mathematics, an equation that contains trigonometric functions is known as trigonometric equations. For example: Cos u = ½. The roots of trigonometric function are obtained by the inverse trigonometric functions. Now see how to solving trigonometric equations. Suppose we have sin u + sin 2u + sin 3u = 0. This trigonometric equation can be reduced to form 2 sin 2u cos u + sin 2u = 0. In other word we can also write as: Sin 2u (2 cos u + 1) = 0. When we solve this equation we get the value of sin 2u as 0.  Sin 2u (2 cos u + 1) = 0;
⇨ Sin 2u = 0. And the value of cos u is:
⇨ 2 cos u + 1 = 0;
⇨ 2 cos u = -1;
⇨ Cos u = -1/2. So the value of cos u is -1/2. This equation gives the result of the trigonometric equations. So u = ½ arcsin 0 = n ⊼/2;
u = arcos (-1/2),
u = 2/3 ⊼ (3n + ½), Where, the value of ‘n’ is either positive or negative integer. Let’s discuss how to solve the trigonometric equations. Let we have the trigonometric equation 4 tan3 u – tan u = 0, that lies in the interval [0, 2⊼]. Then it can be solved as shown below:
So the given trigonometric equation is: 4 tan3 u – tan u = 0. We can write the equation as:
⇨ 4 tan3 u – tan u = 0;
⇨ Tan u (4 tan2 u – 1) = 0, so the value of tan ‘u’ is 0;
Or tan u = + 1/√3. For every value of u ∈ [0, 2⊼],
⇨ Tan u = 0; It means the value of ‘u’ is 0, ⊼ or 2⊼.
While
Tan u = 1/√3,
u = ⊼ / 6 or 7⊼/ 6,
Tan u = -1/√3,
u = 5⊼ / 6 or 11⊼/ 6. This is how we can solve the trigonometric equation. Now we will see the Equation for Velocity. Equation of velocity is given by: Equation of velocity (v) = displacement (D) / time (T). The students of class 1st follow the icse syllabus for class 1.