FINAL TOOLBOX
02 // Visual Math & Finance Solvers(x, y) = (R·cos θ, R·sin θ), cos²θ + sin²θ = 1

Interactive Unit Circle & Six Trig Functions Explorer

The unit circle defines a circle of radius $R = 1$ centered at the Cartesian origin $(0,0)$, where any central angle $\theta$ intersects the circumference at $(x, y) = (\cos\theta, \sin\theta)$ and obeys $\cos^2\theta + \sin^2\theta = 1$.

(x, y) = (R·cos θ, R·sin θ), cos²θ + sin²θ = 1

Inputs & Parameters (3)

°
0°±1360°
u
0.5u±0.255u
×
1×±14×
UNIT CIRCLE (θ = 45°)SIN(kθ) [TEAL] & COS(kθ) [COBALT]cos=0.707sin=0.707
R·cos(θ) [X-Base]
0.7071
cos(45°) = 0.7071
R·sin(θ) [Y-Altitude]
0.7071
sin(45°) = 0.7071
tan(θ) = sin / cos
1
cot(θ) = 1
Radians & Arc Length
0.7854 rad
0.25π rad | Arc s = 0.785

20-Row Comparison Table

Compare across:
#Central Angle (θ) (°)y = R·sin(θ)R·cos(θ)tan(θ)
010 °010
0219 °0.3260.94550.3443
0338 °0.6160.7880.7813
0457 °0.8390.54461.5399
0576 °0.970.24194.0108
0695 °0.996-0.0872-11.4301
07114 °0.914-0.4067-2.246
08133 °0.731-0.682-1.0724
09152 °0.469-0.8829-0.5317
10171 °0.156-0.9877-0.1584
11189 °-0.156-0.98770.1584
12208 °-0.469-0.88290.5317
13227 °-0.731-0.6821.0724
14246 °-0.914-0.40672.246
15265 °-0.996-0.087211.4301
16284 °-0.970.2419-4.0108
17303 °-0.8390.5446-1.5399
18322 °-0.6160.788-0.7813
19341 °-0.3260.9455-0.3443
20360 °-01-0
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Key Analytical Takeaways

  • 01The horizontal base projection (Cobalt) equals $R\cos\theta$, while the vertical altitude drop (Mineral Teal) equals $R\sin\theta$.
  • 02At special benchmark angles ($30^\circ, 45^\circ, 60^\circ$), exact radical ratios ($1/2, \sqrt{2}/2, \sqrt{3}/2$) appear automatically.
  • 03Quadrant sign mnemonic 'All Students Take Calculus' tracks which functions remain positive across Quadrants I, II, III, and IV.

Frequently Asked Questions

Why is the radius set to 1 on the standard unit circle?+

When the hypotenuse R = 1, dividing opposite or adjacent sides by the hypotenuse simplifies directly to y = sin(θ) and x = cos(θ) without extra scaling.

Why does tan(θ) become undefined at 90° and 270°?+

Because tan(θ) = sin(θ) / cos(θ), and at 90° and 270° the x-coordinate cos(θ) equals zero, making the tangent line parallel to the y-axis.

Which trig functions are positive in each quadrant (ASTC rule)?+

Following All-Students-Take-Calculus counterclockwise: all six are positive in Q1 (0°–90°), Sine/Cosecant in Q2 (90°–180°), Tangent/Cotangent in Q3 (180°–270°), and Cosine/Secant in Q4 (270°–360°).