Solveeit Logo

Question

Question: How do you solve \(3\sin x+2=0\)?...

How do you solve 3sinx+2=03\sin x+2=0?

Explanation

Solution

To solve the given equation first we will subtract 2 from both sides of the equation. Then we will divide the obtained equation by 3. We get the value of sinx\sin x. Then by calculating the inverse we get the desired answer.

Complete step by step solution:
We have been given that 3sinx+2=03\sin x+2=0.
We have to solve the given equation.
Now, to solve the given equation first we will subtract 2 from both sides of the equation. Then we will get
3sinx+22=02\Rightarrow 3\sin x+2-2=0-2
Now, simplifying the above obtained equation we will get
3sinx=2\Rightarrow 3\sin x=-2
Now, dividing the above obtained equation by 3 we will get
3sinx3=23\Rightarrow \dfrac{3\sin x}{3}=-\dfrac{2}{3}
Now, simplifying the above obtained equation we will get
sinx=23\Rightarrow \sin x=-\dfrac{2}{3}
Now, taking an inverse function we will get
x=sin1(23)\Rightarrow x={{\sin }^{-1}}\left( -\dfrac{2}{3} \right)
By using the calculator we get the value as
x=0.729c\Rightarrow x={-0.729}^{c}
Hence above is the required answer.

Note: If we get the general value of sinx\sin x which is given in the trigonometric ratio table, it is easy to calculate the value. We can also solve the question in alternative way as:
We get the value by simplifying the equation as
sinx=23\Rightarrow \sin x=-\dfrac{2}{3}
Now, we know that there is no direct value given in the trigonometric ratio table. So when we approximate value we will get
x=41.81\Rightarrow x=-41.81{}^\circ
Or we can write this as
x=180+41.81 x=138.19 \begin{aligned} & \Rightarrow x=-180+41.81{}^\circ \\\ & \Rightarrow x=-138.19 \\\ \end{aligned}
Hence we get the value of x.