{"id":8816,"date":"2017-02-01t11:28:52","date_gmt":"2017-02-01t19:28:52","guid":{"rendered":"\/\/www.catharsisit.com\/hs\/?p=8816"},"modified":"2019-03-17t18:33:02","modified_gmt":"2019-03-18t01:33:02","slug":"ap-calculus-10-step-guide-curve-sketching","status":"publish","type":"post","link":"\/\/www.catharsisit.com\/hs\/ap\/ap-calculus-10-step-guide-curve-sketching\/","title":{"rendered":"ap calculus: 10-step guide to curve sketching"},"content":{"rendered":"
what can calculus tell us about curve sketching? it turns out, quite a lot! in this article, you’ll see a list of the 10 key characteristics that describe a graph. while you may not be tested on your artistic ability to sketch a curve on the ap calculus exams, you will<\/em> be expected to determine these specific features of graphs.<\/p>\n the ten steps of curve sketching each require a specific tool. but some of the steps are closely related. in the list below, you’ll see some steps grouped if they are based on similar methods. <\/p>\n limits<\/strong><\/p>\n first derivative<\/strong><\/p>\n second derivative<\/strong><\/p>\n some books outline these steps differently, sometimes combining items together. so it’s not uncommon to see “the eight steps for curve sketching,” etc.<\/p>\n let’s briefly review what each term means. more details can be found at ap calculus exam review: analysis of graphs<\/a>, for example.<\/p>\n the domain<\/strong> of a function f<\/em>(x<\/em>) is the set of all input values (x<\/em>-values) for the function. <\/p>\n the range<\/strong> of a function f<\/em>(x<\/em>) is the set of all output values (y<\/em>-values) for the function.<\/p>\n methods for finding the domain and range vary from problem to problem. here is a good review<\/a>.<\/p>\n the y<\/em>-intercept<\/strong> of a function f<\/em>(x<\/em>) is the point where the graph crosses the y<\/em>-axis. <\/p>\n this is easy to find. simply plug in 0. the y<\/em>-intercept is: (0, f<\/em>(0<\/em>)).<\/p>\n an x<\/em>-intercept<\/strong> of a function f<\/em>(x<\/em>) is any point where the graph crosses the x<\/em>-axis. <\/p>\n to find the x<\/em>-intercepts, solve f<\/em>(x<\/em>) = 0.<\/p>\n a graph can display various kinds of symmetry. three main symmetries are especially important: even<\/em>, odd<\/em>, and periodic<\/em> symmetry. <\/p>\n the algebraic test for even\/odd is to plug in (-x<\/em>) into the function.<\/p>\n on the ap calculus exams, periodicity occurs only in trigonometric functions. <\/p>\n a vertical asymptote<\/strong> for a function is a vertical line x<\/em> = k<\/em> showing where the function becomes unbounded.<\/p>\n for details, check out how do you find the vertical asymptotes of a function?<\/a>.<\/p>\n a horizontal asymptote<\/strong> for a function is a horizontal line that the graph of the function approaches as x<\/em> approaches ∞ or -∞.<\/p>\n an oblique asymptote<\/strong> for a function is a slanted line that the function approaches as x<\/em> approaches ∞ or -∞.<\/p>\n both horizontal and oblique asymptotes measure the end behavior<\/em> of a function. for details, see how do you find the horizontal asymptotes of a function?<\/a> and how do you find the oblique asymptotes of a function?<\/a>.<\/p>\n a function is increasing<\/strong> on an interval if the graph rises as you trace it from left to right.<\/p>\n a function is decreasing<\/strong> on an interval if the graph falls as you trace it from left to right.<\/p>\n the first derivative measures increase\/decrease in the following way:<\/p>\n the term relative extrema<\/strong> refers to both relative minimum and relative maximum points on a graph.<\/p>\n a graph has a relative maximum<\/strong> at x<\/em> = c<\/em> if f<\/em>(c<\/em>) > f<\/em>(x<\/em>) for all x<\/em> in a small enough neighborhood of c<\/em>.<\/p>\n a graph has a relative minimum<\/strong> at x<\/em> = c<\/em> if f<\/em>(c<\/em>) < f<\/em>(x<\/em>) for all x<\/em> in a small enough neighborhood of c<\/em>.<\/p>\n the relative maxima (plural of maximum)<\/em> and minima (plural of minimum)<\/em> are the “peaks and valleys” of the graph. there can be many relative maxima and minima in any given graph.<\/p>\n relative extrema occur at points where f<\/em> '(x<\/em>) = 0 or f<\/em> '(x<\/em>) does not exist. use the first derivative test to classify them.<\/p>\n concavity is a measure of how curved the graph of the function is at various points. for example, a linear<\/em> function has zero concavity at all points, because a line simply does not curve. <\/p>\n a graph is concave up<\/strong> on an interval if the tangent line falls below the curve at each point in the interval. in other words, the graph curves “upward,” away from its tangent lines.<\/p>\n a graph is concave down<\/strong> on an interval if the tangent line falls above the curve at each point in the interval. in other words, the graph curves “downward,” away from its tangent lines.<\/p>\n here’s one way to remember the definitions: “concave up looks like a cup, and concave down looks like a frown.”<\/p>\n the second derivative measures concavity:<\/p>\n any point at which concavity changes (from up to down or down to up) is called a point of inflection<\/strong>.<\/p>\n any point where f<\/em> ''(x<\/em>) = 0 or f<\/em> ''(x<\/em>) does not exist is a possible point of inflection. look for changes in concavity to determine if these are actual points of inflection.<\/p>\n this short article only outlines the steps for accurate curve sketching. now it’s up to you to familiarize yourself with the various methods and tools that will help you to analyze the graph of any function. <\/p>\n","protected":false},"excerpt":{"rendered":" what can calculus tell us about curve sketching? it turns out, quite a lot! <\/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-8816","post","type-post","status-publish","format-standard","hentry","category-ap","tag-ap-calculus"],"acf":[],"yoast_head":"\n<\/p>\n
guide to curve sketching<\/h2>\n
\nalgebra and pre-calculus<\/strong><\/p>\n
step 1. determine the domain and range<\/h3>\n
step 2. find the y<\/em>-intercept<\/h3>\n
step 3. find the x<\/em>-intercept(s)<\/h3>\n
step 4. look for symmetry<\/h3>\n
\n
\n
step 5. find any vertical asymptote(s)<\/h3>\n
step 6. find horizontal and\/or oblique asymptote(s)<\/h3>\n
step 7. determine the intervals of increase and decrease<\/h3>\n
\n
step 8. locate the relative extrema<\/h3>\n
step 9. determine the intervals of concavity<\/h3>\n
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step 10. locate the inflection points<\/h3>\n
final thoughts<\/h2>\n