First of all, what is the meaning of linear parametric equation?

Its most basic form:

x=a+tcosθ

y=b+tsinθ

Where the parameter is t.

The meanings of constants in this standard equation are as follows: a and b indicate that a straight line passes through a certain point (a, b).

cosθ

Sinθ represents the trigonometric function value of straight line inclination.

Where y= root number 3

x

+2 as an example

Let's randomly select a point (0,2) on it.

Then a = 0 and b = 2.

The inclination angle is 60 degrees.

So cosθ is 1/2.

Sinθ is two-thirds of the root.

From this, the parameter equation can be written: x = 1/2.

t

Y=2+t* the square root of two thirds (t is the parameter)

You can find

a

B is not the only definite value.

in other words

As long as there is a certain point and a certain inclination, a parametric equation can be determined. When t takes different values, different points are determined, and the set of these points is the straight line represented by this parameter equation.

Only by understanding the meaning of the constants of the parametric equation can we master its application skillfully.