We know that the vector quantities are those quantities that have magnitude as well as direction.
Each vector quantity can be divided into two parts a horizontal and vertical component, the vertical component is known as the sine component while the horizontalcomponent is known as the cosine component.
A vector component is the product of its length and the component angle.
Generally, F sinθ is the vertical component and F cosθ is the horizontal component,
Now, from the diagram the horizontal component of vector 'r' is