Pre-Calculus Notes PDF
Document Details
Uploaded by EnergySavingNashville
PNTC Colleges
Tags
Summary
These notes cover conic sections, including circles, ellipses, parabolas, and hyperbolas. They also detail equations for circles, both in standard and general form, and provide examples for solving problems.
Full Transcript
Why conic sections? Architecture Conics in Real life Cathedral de la Canton Tower Resurrection Guangdong Evry , France. Province, China. Architecture Conics in Real life Sydney Harbor Bridge, Sydney , National Radio...
Why conic sections? Architecture Conics in Real life Cathedral de la Canton Tower Resurrection Guangdong Evry , France. Province, China. Architecture Conics in Real life Sydney Harbor Bridge, Sydney , National Radio Australia Astronomy Observatory Charlottesville, Virginia, USA. Architecture Conics in Real life Lyceum of the Philippines University Cavite Campus (x – h)2 + (y - k)2 = r2 x2 + y2 = r2 (center is not in the origin) (center is the origin) where (h, k) is the center and r is the radius Ax2 + By2 + Cx + Dy + E = 0 General form: Ax2 + By2 + Cx + Dy + E = 0 Determine the general form of the equation of a circle: (1) Center at the origin, radius 2 x2 + y2 = r2 standard form of the equation x2 + y2 = 22 substitute the given x2 + y2 = 4 simplify x2 + y2 -4 = 0 General form Determine the general form of the equation of a circle: (2) Center (-1, 2) radius = 𝟑 (x - h)2 + (y - k)2 = r2 standard form of the equation (x + 1)2 + (y-2) 2 = ( 𝟑)2 substitute the given x2 +2x +1 + y2 -4y +4 = 3 simplify x2 + y2 + 2x - 4y +1 +4 - 3 = 0 x2 + y2 +2x -4y +2 = 0 General form Ax2 + By2 + Cx + Dy + E = 0 Given the General Form of Equation of Circle, identify its Center and Radius. Example 1. x2 + y2 -8x + 7 = 0 (x – h)2 + (y - k)2 = r2 x2 -8x + y2 = -7 (x2 – 8x + 16) + y2 = -7 + 16 Completing the Square (x - 4 )2 + y2 = 9 C = (4, 0) r=3 Given the General Form of Equation of Circle, identify its Center and Radius. Example 2. 4x2 + 4y2 + 8x - 8y – 4 = 0 (x – h)2 + (y - k)2 = r2 4x2 + 8x + 4y2– 8y = 4 4(x2 + 2x) + 4(y2– 2y) = 4 4(x2 + 2x+1) + 4(y2– 2y+1) = 4 +1 (4) +1 (4) 4(x+1)2 + 4(y-1)2 = 12 (x+1)2 + (y-1)2 = 3 C = (-1, 1) r = 1.73