Ch 1 Intro to Calculus Simplify Radical Expressions Rationalizing the Denominator Use Limits to Determine the slope and the equation of the tangent to a graph The process of changing a denominator from a radical (square root) to a rational number (integer) Slope of Tangent To rewrite a radical expression with a oneterm radical in the denominator, multiply the numerator and denominator by the one-term denominator. The slope of the tangent to a curve at a point P is the limiting slope of the secant PQ as the point Q slides along the curve toward P. When the denominator of a radical fraction is a two-term expression, you can rationalize the denominator by multiplying by the conjugate. In other words, the slope of the tangent is said to be the limit of the slope of the secant as Q approaches P along the curve. Slope of a Tangent as a Limit Avg and Instantaneous Rate of Change Related to Slope of Secants and Tangents The slope of the tangent to the graph y = f( x) at point P(a, f(a)) is as the equation shows if the limit exists. Instantaneous Velocity Understand and Evaluate Limits Using Appropriate Properties The velocity of an object with position function s(t), at time t = a, is as the equation shows. Limits and Their Existence Average Rate of Change We say that the number L is the limit of a function y f1x2 as x approaches the value a, written as the equation shown above. Otherwise, the limit does not exists. The difference quotient, shown above, is called the average rate of change in y with respect to x over the interval from x = a to x = a + h. Instantaneous Rates of Change There are some cases that we need to remember. Therefore, we can conclude that the instantaneous rate of change in y = f(x) with respect to x when x = a is the equation shown above, provided that the limits exists. Properties of the Limit Examine continuous Functions Using Limits If f is a polynomial function, then as it shown above. Substituting x = a into the limit can yield the indeterminate from 0 / 0. If this happens, you may be able to find an equivalent function that is the same as the function f got all values except at x = a. Then, substitution can be used to find the limit. Continuity at a Point To evaluate a limit algebraically, we can used: The function f(x) is continuous at x = a if f(a) is defined and if the equation shows above. Otherwise, f(x) is discontinuous at x = a. Types of discontinuity direct substitution factoring Point - a hole rationalizing Jump - piecewise functions one-sided limits Infinite - vertical asymptote change of variable Defined Continuity Things need to know for continuity All polynomial functions are continuous for all real numbers. A rational function as shown above is continuous at x = a if g(a) no equal to 0. A rational function in simplified form has a discontinuity at the zeros of the denominator. When the one-sided limits are not equal to each other, then the limit at this point does not exist and the function is not continuous at this point. f(a) is defined