1019 past contests
Topic 9 · Finding the prime numbers between $80$ and $90$
Topic 13 · General term of $-5,\ -2,\ 1,\ 4,\ 7,\ \ldots$
Topic 42 · Evaluating $\dfrac{\tan87^\circ-\tan42^\circ}{1+\tan87^\circ\tan42^\circ}$
Topic 36 · Identifying the regular polygon with interior angle $\dfrac{5\pi}{6}$ radians
Topic 9 · Riddle: a four-digit odd palindrome $abba$ where $b^2=a$
Topic 42 · Does $\sin x$ increase steadily on $0\lt x\lt\pi$? (true/false)
Topic 42 · Does $\sin x$ decrease steadily on $0\lt x\lt\pi$? (true/false)
Topic 42 · Does $\sin x$ both increase and decrease on $0\lt x\lt\pi$? (true/false)
Topic 35 · Diagonals of a parallelogram bisect each other (true/false)
Topic 35 · Diagonals of a rhombus are perpendicular and bisect the vertex angles (true/false)
Topic 34 · The diagonals of a rectangle form two pairs of congruent triangles (true/false)
Topic 8 · Finding $x+y+z$ from $\log_2(\log_3(\log_4x))=0$ and two similar equations
Topic 11 · Image of $a(-2,1)$ under the translation mapping $(3,5)$ onto $(5,6)$
Topic 8 · Combining $5\log x-3\log y+4\log z$ into a single logarithm
Topic 42 · Evaluating $2\cos^2(15^\circ)-1$
Topic 11 · Matrix for $(x,y)\mapsto(x,-y)$ (reflection in the $x$-axis)
Topic 11 · Matrix for $(x,y)\mapsto(-x,y)$ (reflection in the $y$-axis)
Topic 11 · Matrix for $(x,y)\mapsto(y,x)$ (reflection in the line $y=x$)
Topic 19 · Maximum or minimum point of $y=x^2+4x+5$
Topic 19 · Maximum or minimum point of $y=2x^2-4x+5$