What you’ll learn6 learning objectivesChoose one objective for a focused lesson, or study the complete topic.—SL 2.1—Straight lines• Use gradient, intercepts and forms of a straight line.• Know parallel gradients m1=m2 and perpendicular gradients m1m2=-1.Syllabus objective—SL 2.2—Functions and inverses• Understand function, domain, range, graph and function notation.• Interpret functions as mathematical models.• Inverses undo functions, reflect in y=x and exist for one-to-one functions.Syllabus objective—SL 2.3—Graphing functions• Draw/sketch graphs from equations, contexts or technology.• Label axes and key features, including sums and differences of functions.Syllabus objective—SL 2.4—Key graph features• Determine maxima, minima, intercepts, symmetry, vertex, roots/zeros and asymptotes.• Use technology to find intersections of curves or lines.Syllabus objective—SL 2.5—Modelling with functions• Use linear, piecewise linear, quadratic, exponential, direct/inverse variation, cubic and sinusoidal models.• Interpret key parameters such as roots, vertex, asymptotes, amplitude, period and principal axis.• Use technology where appropriate to find roots and fit or interpret models.Syllabus objective—SL 2.6—Modelling process• Choose an appropriate model and reasonable domain for a context.• Find model parameters using technology, initial conditions or substitution of points.• Test, reflect on, interpret and use models; recognize dangers of extrapolation.Syllabus objective