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IGCSE Mathematics - Equations

Equations

October 19, 2022

Equations

Difference of squares

(a+b)(a-b) = a2 - b2

Identities and Equations

2x+x=3x is an identity because it is true for all values of x

2x+1=3 is an equation because it is only true for x=1

If an equation contains fractions,then you cross-multiply to remove the brackets.

FOLI:

In IGCSE Mathematics curriculum, if there are three brackets, multiply out the first two brackets then multiply by the remaining bracket

Graphs

  • A quadratic graph is called a parabola
  • A parabola has a vertical line of symmetry and is infinite
  • Cubic graphs have x3 as the highest power and will look similar to this

Gradient

The equation of a straight line is y=mx+c where m is the gradient and c is the y intercept

If the gradient of a straight line is m,the gradient of the line perpendicular to m is -1/m

Standard index form

In IGCSE Mathematics currciculum, standard index form can be used to express very large or very small quantities

For example:

  • 524 = 5.24x102
  • 0.0467 = 4.67x10-2

End of this topic!

Drafted by Gina (Mathematics)