HSC Maths Standard 2 exam 2026Exam: Mon 19 Oct · NESA timetable

A sector angle is the data's fraction of a full turn:

Straight-line (prime-cost) depreciation removes the same amount $D$ every year, so value
plots as a falling straight line from the purchase price:

Simple interest plots as a straight line. Interest against time goes through the
origin; amount against time starts at the principal $P$. Either way the
gradient is the interest each period, $Pr$:

Simple interest is charged on the original principal only, so it is the same
amount each period.

GST is a fixed $10\%$, so it is really just three uses of the multiplier $1.1$.

Every probability satisfies $0 \le P(E) \le 1$: impossible scores $0$, certain scores $1$. An event and its complement fill the whole sample space and add to $1$, so

Tree diagrams: multiply probabilities along the branches of a path (AND), and add the probabilities of separate mutually exclusive paths (OR). Every set of branches from a node sums to $1$, and so do all the complete paths.

A tree is a connected graph with no cycles. Equivalently, it is a connected graph in which there is exactly one path between every pair of vertices. A spanning tree of a connected graph is a tree that uses all of the graph's vertices.

Maximum-flow minimum-cut theorem. In any flow network, the maximum flow from source to sink equals the capacity of the minimum cut (the cut of smallest capacity). So to find the maximum flow, find the cut with the least total source-to-sink capacity, and that number is the answer.

Float $= \text{LST} - \text{EST} = \text{LFT} - \text{EFT} = L_j - E_i - t$. An activity is critical exactly when its float is zero, so on a per-activity EST $\mid$ LST box the critical activities are the ones whose two numbers are equal. The critical path is the chain of those equal-number boxes from start to finish.

A Venn diagram for two attributes $A$ and $B$ has four regions: $A$ only, both, $B$ only, and neither. Fill the overlap first, then subtract it from each circle total:

Every scatterplot answer states three things: form (linear or non-linear), direction (positive, negative or none) and strength (how tightly the points hug the pattern), plus any outliers. Independent variable on the $x$-axis, dependent on the $y$-axis. Plot the dots; never join them.

$r$ lives in $[-1, 1]$. The sign is the direction (positive or negative) and the magnitude $|r|$ is the strength (closer to $1$ is stronger, closer to $0$ is weaker). A full interpretation always names all three things: strength, direction, and the word "linear". $r$ only detects straight-line association.