High School 1 mathematics
Step 7 covers High School 1. Fifteen activities from this grade are now translated into English, with the same quizzes and best-score tracking as the Korean site — more High School 1 topics are on the way.
🔢 Number & operations
Binomial Expansion & Remainder Theorem
Match (a+b)ⁿ's coefficients to Pascal's Triangle, then verify the remainder theorem with synthetic division.
Open English lesson → ∩Sets & Propositions
Mark out Venn diagram regions with set operations, then compare a proposition's converse, inverse, and contrapositive.
Open English lesson → ➕Imaginary & Complex Numbers
From i²=−1 to polar form and Euler's formula, with a 10-question quiz.
Open English lesson → 🧩Binomial Squares, Factoring & Quadratics
See the binomial square formula as area, then find a quadratic equation's roots by factoring.
Open English lesson → 🧮Various Equations & Inequalities
Systems of quadratic equations, systems of inequalities, and absolute-value equations and inequalities, all in one lab.
Open English lesson → 🧩Factoring Area Puzzle Lab
Explore how x²+bx+c can be factored into (x+p)(x+q) using a visual rectangle-area model.
Open English lesson →📈 Functions & graphs
Linear Function Graph
Adjust the slope and y-intercept and watch the line move in real time.
Open English lesson → 📈Quadratic Function Graph
Adjust a, b, and c and watch the parabola and its vertex move in real time.
Open English lesson → 📉Equation of a Line
Move two points and watch the slope and equation update live, with parallel and perpendicular conditions.
Open English lesson → 🧩Quadratic Inequality
See where a parabola sits above or below the x-axis, then solve quadratic inequalities yourself with a quiz.
Open English lesson → 🔀Various Functions Lab
Rational and irrational function graphs, plus composite and inverse functions with a function-machine diagram.
Open English lesson → ⭕Equation of a Circle
Build the equation of a circle from its definition, then explore how a circle and a line can meet.
Open English lesson → 📉Quadratic Function Max/Min on a Restricted Domain Lab
When the range of x is restricted, see for yourself whether the maximum and minimum of a quadratic function occur at the vertex or at one of the endpoints.
Open English lesson → ⚖️Relationship Between Roots and Coefficients of a Quadratic Equation Lab
See how you can find the sum and product of the two roots directly from the coefficients without solving the quadratic equation itself.
Open English lesson → 📏Section Formula Lab
Use sliders to explore the coordinates of the point that divides a line segment connecting two points in a chosen ratio.
Open English lesson →📐 Trigonometry
Law of Sines & Law of Cosines
Solve any triangle — not just right triangles — from just a few known angles and sides.
Open English lesson → 🏢Applying Trig Ratios
Find a triangle's area from two sides and an angle, and measure a building's height without a ruler.
Open English lesson → ⚙️Rolling Circle Around Shapes: Center Locus Lab
Roll a circle once around a polygon or a row of circles and directly explore the length of the path traced by its center. You can also see how the circle moves…
Open English lesson →🔢 Matrices
📊 Probability & statistics