May 6, 2026
1000 North Marshall Street, USA

For your HKDSE mathematics revision, a particularly "useful feature" for mastering Graph Transformations "Inside vs. Outside" rule

  • Equation: $y = f(-x)$
  • Transformation: The graph is flipped horizontally.
  • Mechanism: Every $x$-coordinate changes sign ($x \rightarrow -x$), while $y$-coordinates remain unchanged.

    Solution

    (a) ( y = f(x) + 3 )
    (b) ( y = f(x - 2) )
    (c) ( y = f(x + 1) - 4 )

    3. Worked Examples (DSE Style)

    Example 1: Combined Transformation

    Given ( f(x) = x^2 ), sketch ( g(x) = -2f(x+1) + 3 ).