Formula classification Formula expression multiplication and factorial A2-B2 = (a+b) (a-b) A3+B3 = (a+b) (A2-AB+B2) A3-B3 = (A-B (A2+AB+B2) Trigonometric inequality | A+B |≤| A. = -b ≤ a ≤ b | a-b |≥| a |-b |-a |≤ a | the solution of a quadratic equation with one variable -b+√(B2-4ac)/2a-b-√(B2-4ac)/2a root and the coefficient x 1+. 0 Note: The equation has two unequal real roots b2-4ac0 parabola standard equation Y2 = 2px2 =-2px2 =-2py straight prism lateral area S=c*h oblique prism lateral area S = c'* h right pyramid lateral area S = 1/2c * h' right pyramid lateral area S = 1/2. H' frustum side area S= 1/2(c+c')l=pi(R+r)l surface area of sphere S=4pi*r2 cylindrical side area S=c*h=2pi*h conical side area s =1/2 * c * l = pi *.