Tabulation method
method of images
Proportional function: y=kx(k is constant, k≠0)
When k>0, the image passes through one or two quadrants, and y increases with the increase of x.
When k < 0, the image passes through two or four quadrants, and y decreases with the increase of x.
Linear function: y=kx+b(k, b is constant, k≠0)
When b=0, y=kx+b = y=kx, so the proportional function is a special form of linear function.
Inverse proportional function: y=k/x(k is constant, k≠0)
Quadratic function: y=ax+bx+c(a, b and c are constants a≠0)
Acute trigonometric function:
Definition of sine: opposite side/hypotenuse of sine = ∠ a = a/c.
Cosine definition: adjacent side/hypotenuse of cosine = ∠ A = B/C.
Tangent definition: Tana =∠A the opposite side of ∠ A/the adjacent side of ∠ A = A/B.