= 0.0 1 cos4t-0.0 1 *√3 sin4t

=0.02cos(4t+π/3)

Another solution: x2=-0.03cos(4t+π/3)

∴x=x 1+x2=0.02cos(4x+π/3)

or

X=x 1+x2 expand two cos by trigonometry.

x 1 = 4 cos(2πzhit)* cos(π/3)-4 sin(2πt)* sin(π/3)

=2cos(2πt-2*sqr(3)4sin(2πt)

Similarly, x2 is also extended,

The two want to add up and merge.

Then the auxiliary angle is formulated as a trigonometric function. Both amplitude and initial phase are available.

Extended data:

According to this equation of motion, we can say that the motion of sine or cosine function whose displacement is time t is simple harmonic motion, and simple harmonic motion's mathematical model is a linear ordinary differential equation with constant coefficients. This kind of vibration system is called linear system. Linear system is the simplest and most common mathematical model of vibration system. But generally speaking, linear system is only an approximate model of vibration system under the condition of small amplitude.

Baidu Encyclopedia-simple harmonic motion