This chapter is very much ‘alive’ for those who are seating for the coming SPM…eventhough not much focus being made on it at PMR level. For those who wish to master this chapter, please take note on the following factors :-

a.   Understand the basic concept of equation

  • Equation of straight line is represented by y = mx + c; where m = gradient  and c = y intercept
  • Equation of curve is represented by y = ax² + bx + c
  • NOTE THAT y OR/AND x CAN BE REPRESENTED BY OTHER FORM SUCH AS f(x), log y etc

b.   Understand the 4 basic ways of finding gradient

  • m = difference of y / difference of x when minimum of 2 coordinates are known
  • differentiate the equation by way of dy/dx when only 1 coordinate is given (this step is learnt in Add Maths)
  • gradient for perpendicular line is calculated as -1/ gradient of ordinary straight line (m1 x m2 = -1)
  • gradient of normal = gradient of perpendicular line

c.   Know the shape of equations

  • +ve or -ve gradient is reflected differently when plotted into a graph (y = +ve or -ve mx + c)
  • +ve or -ve value of a is reflected differently when plotted into a graph (y = +ve or -ve ax² + bx + c)

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Bear in mind that this chapter may also require knowledge and understanding from other chapters such as logarithm, algebra, coordinate geometry, trigonometry and many more.