Mathematical Operations
🔒 Log in to trackmedium importance~1-2 Q in Tier 15 formulas⚡ 6 shortcuts5 subtopics
Every formula in this topic, grouped by subtopic. Print it and pin it above your desk.
Operator puzzles and BODMAS
BODMAS order
B \to O \to D/M \to A/S
D and M share a rank and go left to right; so do A and S.
Missing number
? = \dfrac{\text{RHS} - \text{loose terms}}{\text{factor}}
Undo + and − first, then the multiply or divide around the ?.
Hidden-rule and defined operations
Sum of squares
a \# b = a^2 + b^2
A very common hidden rule: 5 # 3 = 34.
Difference of squares
a @ b = a^2 - b^2
Also equals (a+b)(a−b): 8 @ 2 = 60.
Product plus sum
a \diamond b = ab + a + b
Multiply, then add both numbers: 4 ◇ 3 = 19.