Evaluating Limits with Trigonometric Functions
Ever wondered how to tackle those tricky limits with sine functions? The limit of sin(x)/x is a classic problem that appears frequently in calculus exams.
To evaluate lim (x→a) sin(x)/x, we can use the Pythagorean identity sin²(x) + cos²(x) = 1. This identity gives us a powerful tool to transform the expression into something more manageable.
The strategy involves multiplying both numerator and denominator by the same expression to create a useful pattern. In this case, we multiply by cos(x)/cos(x), which equals 1 and doesn't change the value. This gives us:
lim (x→a) sin(x)/x * cos(x)/cos(x) = lim (x→a) (sin(x)∗cos(x))/(x∗cos(x))
💡 When stuck on a limit problem, look for opportunities to multiply by a strategic form of 1 likecos(x)/cos(x) that can help simplify the expression!