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Find the derivatives of various functions using different methods and rules. Several Examples with detailed solutions are presented. More exercises with answers are at the end of this page.
Example 1: Find the derivative of function f given by
Solution to Example 1:
- Function f is the product of two functions: U = x 2 - 5 and V = x 3-2x+3. We use the product rule to differentiate f as follows:
- Expand and group to obtain
Example 2: Calculate the first derivative of function f given by
Solution to Example 2:
- This function may be considered as the product of function U = sqrt x + 2x and V = 4x2 - 1, hence the use of the product rule
- To add the above you need to write all terms as fractions with a common denominator.
- Expand
- and group to obtain the final result for the derivative of f as follows.
Example 3: Calculate the first derivative of function f given by
Solution to Example 3:
- The given function may be considered as the ratio of two functions: U = x2 + 1 and V = 5x - 3 and use the quotient rule to differentiate f is used as follows
- Expand and group to obtain f'(x) as follows
Example 4: Calculate the first derivative of function f given by
Solution to Example 4:
- Function f is the quotient of two functions hence the use of the quotient rule
- Write all terms in the numerator so that they have the same denominator 2 sqrt x
- Expand and group like terms to obtain f'(x)
Example 5: Calculate the first derivative of function f given by
Solution to Example 5:
- Function f given above may be considered as the product of functions U = 1/x - 3 and V = (x2 + 3)/(2x - 1), and function V may be considedered as the quotient of two functions x2 + 3 and 2x - 1. We use the product rule for f and the quotient rule for V as follows
- Set all terms to a common denominator
- Expand and group to obtain the derivative f'.
Example 6: Calculate the first derivative of function f given by
Solution to Example 6:
- There are several ways to find the derivative of function f given above. One of them is to consider function f as the product of function U = sqrt x and V = (2x - 1)(x3 - x) and also consider V as the product of (2x - 1) and (x3 - x) and apply the product rule to f and V as follows
- Set a common denominator to all terms
- Expand and group like terms to obtain the derivative f'.
Example 7: Find the derivative of function f given by
Solution to Example 7:
- The given function is of the form U4 where U = x3 + 4. The use of the chain rule of differentiation gives f ' as follows
- Calculate U ' and substitute above to obtain f ' as follows
Example 8: Find the derivative of function f given by
Solution to Example 8:
- Function f is of the form U3 where U = (x - 1) / (x + 3). Apply the chain rule to obtain f ' as follows
- Calculate U ', using the quotient rule, and substitute to obtain
- Expand and group like terms to obatin a final form for the derivative f '
Example 9: Find the derivative of function f given by
Solution to Example 9:
- The given function is of the form sqrt U with U = x3 + 2 x + 1. Calculate U ' and use the chain rule to obtain
Example 10: Find the derivative of function f given by
Solution to Example 10:
- The given function is of the form U3/2 with U = x2 + 5. Apply the chain rule as follows
- Calculate U ', substitute and simplify to obtain the derivative f '.
Example 11: Find the derivative of function f given by
Solution to Example 11:
- Function f is of the form U1/4 with U = (x + 6)/(x + 5). Use the chain rule to calculate f ' as follows
- Since U is the quotient of two function, use the quotient rule to find U ' and substitute to obtain
- Expand and group like terms
- Change the negative exponent into a positive exponent to find a final form of f ' as follows
Exercises: Find the derivative of each of the following functions.
Answers to Above Exercises:
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differentiation and derivatives
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