====== Gallery of Curves ====== ==== Straight Line ==== {{ straight_line.png|Straight Line}} $$y = ax + b$$ where $a$ is the slope, and\\ $b$ is the y-intercept. ~CLEAR~ ==== Conic Section ==== == Circle == {{cone_circle.png |Conic Section Circle}} {{ unit_circle.png|Circle}} $$x^2 + y^2 = r^2$$ Unit Circle: $$x^2 + y^2 = 1$$ $$(x+a)^2 + (y+b)^2 = r^2$$ ~CLEAR~ == Ellipse == {{cone_ellipse.png |Conic Section Ellipse}} {{ ellipse.png|Ellipse}} $$\frac{x^2}{a^2} + \frac{y^2}{b^2} = 1$$ ~CLEAR~ == Parabola == {{ parabola.png|Parabola}} $$y = x²$$ A function with a second order nomial x² will have a parabolic shape,\\ concave if positive, convex if negative Axis of symmetry. ~CLEAR~ == Hyperbola == {{ hyperbola.png|Hyperbola}} $$y = \frac{1}{x}$$ Not to be confused with [[hyperbole]], an exaggeration used as a figure of speech, like "it weighs a ton". Applications from wikipedia.\\ Path of sundial shadow.\\ Orbit of asteroid.\\ ~CLEAR~ ==== Sigmoid ==== {{ sigmoid.png|Sigmoid}} $$ y = \frac{1}{1+e^{x}}$$ y is always between 0 and 1.\\ s-shaped curve as in "sigmoid".\\ asymptotes to 0 to the left and 1 to the right.\\ ~CLEAR~ ==== Polynomials ==== {{ polynomial_0_degree.png|Polynomial 0 Degree}} $$y = x² + 2ax + b$$ {{ polynomial_1_degree.png|Polynomial 1 Degree}} {{ polynomial_2_degree.png|Polynomial 2 Degree}} {{ polynomial_3_degree.png|Polynomial 3 Degree}} {{ polynomial_4_degree.png|Polynomial 4 Degree}} {{ polynomial_x.png|Polynomial x}} {{ polynomial_xx.png|Polynomial xx}} | {{ polynomial_xxx.png|Polynomial xxx}} {{ polynomial_xxxx.png|Polynomial xxxx}} ~CLEAR~ {{cone_ellipse.png |Conic Section Circle}} {{cone_ellipse.png |Conic Section Circle}} {{cone_ellipse.png |Conic Section Circle}} {{cone_ellipse.png |Conic Section Circle}} {{quadratic_1.png|Quadratic 1}} {{quadratic_2.png|Quadratic 2}} {{quadratic_3.png|Quadratic 3}} ~CLEAR~ ===== Spirals ===== {{archimedes_spiral.png|Archimedes Spiral}} {{logarithmic_spiral.png|Logarithmic Spiral}} {{helix.png|Helix}} ==== References ==== * Scripts for these graphs are found in http://samantha.voyc.com/doc/script * For more, see https://en.wikipedia.org/wiki/Gallery_of_curves. * Khan Academy playlist: https://www.youtube.com/playlist?list=PLQPuPO-ipSuhNoqOUXasI1mAzSXubTv3z ==== Notes ==== Movement\\ Growth\\ Acceleration\\ cone \\ cone sliced by planes \\ conic section: circle, ellipse, parabola, hyperbola equation of a plane\\ https://www.maplesoft.com/support/help/maple/view.aspx?path=MathApps%2FEquationofaPlane3Points solving linear equations\\ 3 planes in one cube\\ https://en.wikipedia.org/wiki/System//of//linear_equations\\ https://en.wikipedia.org/wiki/Linear_algebra\\ parametric equations\\ http://mathworld.wolfram.com/ParametricEquations.html linear regression, multiple parameters\\ $$y = x₁w₁ + x₂w₂ + x₃w₃ + b$$