📐 Mathematics · Topic 158 of 200

Graph of Tangent

Tangent repeats every π and has vertical asymptotes.

Interactive labDrag the sliders and hover over the graph

About this topic

The tangent graph, y = tan x, has period π and vertical asymptotes wherever cos x = 0, at x = π/2 + nπ. Between asymptotes it rises from −∞ to +∞ through the origin, so its range is all real numbers.

It is odd and has no amplitude. Tangent is the slope of the terminal ray of an angle, or sin x divided by cos x, so it blows up whenever the denominator is zero and equals zero whenever sine is zero. Its zeros are at multiples of π, and it equals 1 at π/4 and −1 at −π/4.

Example: at 89° the tangent is about 57, and at 89.9° it is about 573, showing the rapid growth toward the asymptote at 90°. A hill that rises 1 metre per metre horizontally has slope 1, an angle of 45°; as the slope grows without limit the angle approaches 90°.

Tangent graphs appear in modelling slopes, camera angles and rotating beacons shining on a wall. Students often draw the curve crossing the asymptotes; it never does. Also remember that tan has period π, not 2π, so the pattern repeats twice as fast as sine and cosine.

Key ideas

  1. tan x = sin x / cos x
  2. Asymptotes at π/2 + kπ
  3. Range is all real numbers

Quick check

Use cases: where Graph of Tangent helps

Number and algebra skills are used in science, engineering, budgeting and computing.

Frequently asked questions

What is Graph of Tangent?

Tangent repeats every π and has vertical asymptotes.

What will I learn in Graph of Tangent?

tan x = sin x / cos x. Asymptotes at π/2 + kπ. Range is all real numbers.

Is Graph of Tangent part of Mathematics?

Yes. It is one of 200 Mathematics topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.

Does the Graph of Tangent lab work on a phone or tablet?

Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.

How should I study Graph of Tangent?

Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.

Do I need an account, and is my progress saved?

No account is needed. Marking a topic as learned is saved in your own browser, so it stays on that device and is not sent to a server.

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