Question

how to learn formula of surface area​

Answer 1

The most easiest way to remember anything is to practice them with smart strategy.

If you know area of circle then volume of cylinder and hence the volume of cone can be derived in no time.

If you know area of triangle you may know area of pyramid and prism.

If you know area of rectangle you may easily recall area of square,area of trapezium, volume of trapezoid, volume of cube and cuboid.

Learn as you practice…..