the path of a rocket can be modeled using parametric equations (cc0 public domain)<\/figcaption><\/figure>\na parametric function<\/strong> is a set of two (or more) functions all defined in terms of the same parameter<\/strong> (usually t<\/em> for time). we usually express a parametric function as a list, x<\/em> = f<\/em>(t<\/em>), y<\/em> = g<\/em>(t<\/em>).<\/p>\na vector function<\/strong> is the same concept except in the form of a vector<\/strong>: (f<\/em>(t<\/em>), g<\/em>(t<\/em>)).<\/p>\nexample<\/h3>\n here is a typical parametric function:<\/p>\n
<\/p>\n
and the same expression written as a vector function:<\/p>\n
<\/p>\n
both of the above functions have the same graph, which is an ellipse. most graphing calculators are capable of graphing parametric functions.<\/p>\ngraph of (3 cos t<\/em>, 2 sin t<\/em>)<\/figcaption><\/figure>\nderivatives of parametric functions<\/h2>\n if x<\/em> = f<\/em>(t<\/em>) and y<\/em> = g<\/em>(t<\/em>) define a parametric function, then we find the derivative by the formula,<\/p>\n <\/p>\n
example<\/h3>\n find the slope of the ellipse (3 cos t<\/em>, 2 sin t<\/em>) at t<\/em> = π\/3.<\/p>\n <\/p>\n
plugging in the given t<\/em> = π\/3, <\/p>\n <\/p>\n
velocity and acceleration vectors<\/h2>\n if (f<\/em>(t<\/em>), g<\/em>(t<\/em>)) define the position of an object in terms of time t<\/em>, then the following expressions define the velocity<\/strong> and acceleration<\/strong> vectors of the function at time t<\/em>.<\/p>\n <\/p>\n
note that the velocity vector involves the first derivatives while the acceleration vector involves second derivatives.<\/p>\n
example<\/h3>\n with our running example, the ellipse equations, we can derive expressions for the velocity and acceleration of an object traveling along the ellipse.<\/p>\n
<\/p>\n
length of parametric curves<\/h2>\n the formula for the length<\/strong> of a parametric curve x<\/em> = f<\/em>(t<\/em>) and y<\/em> = g<\/em>(t<\/em>) from t<\/em> = a<\/em> to t<\/em> = b<\/em> is:<\/p>\n <\/p>\n
example<\/h3>\n set up the formula for the length of the semi-ellipse defined by (3 cos t<\/em>, 2 sin t<\/em>) where 0 ≤ t ≤ π.<\/p>\ngraph of the semi-ellipse<\/figcaption><\/figure>\nusing the formula for the length of a curve:<\/p>\n
<\/p>\n
summary<\/h2>\n multivariables only show up on the ap calculus bc exam, and only in the form of parametric or vector functions. the topics you should be aware of include:<\/p>\n
\ngraphing and interpreting graphs of parametric functions<\/li>\n finding the slope of a parametric function at a given point<\/li>\n finding velocity and acceleration vectors<\/li>\n computing the length of a parametric curve<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"what are multivariables? in this short review article you’ll discover what you need to know about multivariables for the ap calculus bc exam!<\/p>\n","protected":false},"author":223,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[240],"tags":[241],"ppma_author":[24932],"class_list":["post-9347","post","type-post","status-publish","format-standard","hentry","category-ap","tag-ap-calculus"],"acf":[],"yoast_head":"\n
ap calculus review: multivariables - magoosh blog | high school<\/title>\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n\t \n\t \n\t \n