28. Integration of 1 / (x^5 + 1)
28. Integration of 1 / (x^5 +Â 1)
Question. (a) By using partial fractions, show that where (b) Hence, or otherwise, show that where (c) Hence, or otherwise, show that
Solution. (a) (1) Factorisation of the denominator
For the second factor, we seem to have two options:
The first line gives
while the second line yields
Since the second line gives two complex conjugate roots, we select the first one and…
View On WordPress
0 notes
27. Integration of 1 / (x^4 + 1)
27. Integration of 1 / (x^4 +Â 1)
Question. (a) By using partial fractions, show that (b) Hence, or otherwise, show that (c) Hence, or otherwise, show that
Solution. (a) (1) Factorisation of the denominator: Can think of two possibilities:
For real values of , we have to choose the first line with (the second line gives complex values for ):
i.e.
(2) Partial fractions
Solving four simultaneous equations
gives
Finally,
(b)…
View On WordPress
0 notes
35. Integration of 1/(x^3+1)
35. Integration of 1/(x^3+1)
Question. (a) By using partial fractions, show that (b) Hence, or otherwise, show that (c) Hence, or otherwise, show that
(a) (1) Factorisation of the denominator
(2) By partial fractions,
By the method of substitution (can equally use the method of equating the coefficients)
which gives
Hence,
(b) Integration
For the last part, we use the following substitution:
which gives
Finally, we…
View On WordPress
0 notes
24. Integration of general powers of sine and cosine functions (feat. Euler beta and gamma functions)
24. Integration of general powers of sine and cosine functions (feat. Euler beta and gamma functions)
Question 1. Let (a) By integration by parts where and , show that (b) By integration by parts where and , show that Â
Solution. (a) By integration by parts,
we find
(b) By integration by parts,
we find
Question 2. Let (a) By the substitution: , show that where the Euler beta function, also known as the Euler integral of the 1st kind, is defined by and the Euler gamma function, also known as…
View On WordPress
0 notes
28. Relations between trigonometric functions
28. Relations between trigonometric functions
1. Relations between trigonometric functions
The inter-relations are obtained by the following identities:
in terms of––––––
2. Relations between the inverse trigonometric functions
The following results are collected while working out compositions of trigonometric and inverse trigonometric functions.
written as––––––
View On WordPress
0 notes
Compositions of trigonometric and inverse trigonometric functions (35)
Compositions of trigonometric and inverse trigonometric functions (35)
Proof of (35). Method 1. We can take the reciprocal of (17):
Method 2. Let where and , , i.e.
What we want is in terms of , so our strategy is to express in terms of using trigonometric identities.
View On WordPress
0 notes
Compositions of trigonometric and inverse trigonometric functions (34)
Compositions of trigonometric and inverse trigonometric functions (34)
(34) Method 1. We can take the reciprocal of (16):
Method 2. Let where and , , i.e.
What we want is in terms of , so our strategy is to express in terms of using trigonometric identities.
View On WordPress
0 notes
23. Integration of general powers of cosine function (A generalisation of Wallis integral)
23. Integration of general powers of cosine function (A generalisation of Wallis integral)
Question. Let (a) By the substitution , show that where the Euler beta function, also known as the Euler integral of the 1st kind, is defined by and the Euler gamma function, also known as the Euler integral of the 2nd kind, is defined by Also, we note the following properties (see here for more details), (b) Using the recurrence relation, , show that where denotes the set of positive integers…
View On WordPress
0 notes
Compositions of trigonometric and inverse trigonometric functions (33)
Compositions of trigonometric and inverse trigonometric functions (33)
Proof of (33). Method 1. We can take the reciprocal of (15):
Method 2. Let where and , i.e.
What we want is in terms of , so our strategy is to express in terms of using trigonometric identities.
View On WordPress
0 notes
Compositions of trigonometric and inverse trigonometric functions (32)
Compositions of trigonometric and inverse trigonometric functions (32)
Proof of (32). Method 1. We can take the reciprocal of (14):
Method 2. Let where and , i.e.
What we want is in terms of , so our strategy is to express in terms of using trigonometric identities.
View On WordPress
0 notes
Compositions of trigonometric and inverse trigonometric functions (31)
Compositions of trigonometric and inverse trigonometric functions (31)
Proof of (31). Method 1. We can take the reciprocal of (13):
Method 2. Let where and , i.e.
What we want is in terms of , so our strategy is to express in terms of using trigonometric identities.
View On WordPress
0 notes
22. Integration of general powers of sine function (Generalisation of Wallis integral)
22. Integration of general powers of sine function (Generalisation of Wallis integral)
Question. Let (a) By the substitution , show that where the Euler beta function, also known as the Euler integral of the 1st kind, is defined by and the Euler gamma function, also known as the Euler integral of the 2nd kind, is defined by Also, we note the following properties (see here for more details),  (b) Using the recurrence relation, , show that where denotes the set of positive integers…
View On WordPress
0 notes
Compositions of trigonometric and inverse trigonometric functions (30)
Compositions of trigonometric and inverse trigonometric functions (30)
Proof of (30). Method 1. We can take the reciprocal of (6):
Method 2. Let where and , i.e.
What we want is in terms of , so our strategy is to express in terms of using trigonometric identities.
View On WordPress
0 notes
Compositions of trigonometric and inverse trigonometric functions (28)
Compositions of trigonometric and inverse trigonometric functions (28)
Proof of (28). Method 1. We can take the reciprocal of (4):
Method 2. Let where and , , i.e.
What we want is in terms of , so our strategy is to express in terms of using trigonometric identities.
View On WordPress
0 notes
Compositions of trigonometric and inverse trigonometric functions (27)
Compositions of trigonometric and inverse trigonometric functions (27)
Proof of (27). Method 1. We can take the reciprocal of (3):
Method 2. Let where and , i.e.
What we want is in terms of , so our strategy is to express in terms of using trigonometric identities.
View On WordPress
0 notes
Compositions of trigonometric and inverse trigonometric functions (26)
Compositions of trigonometric and inverse trigonometric functions (26)
Proof of (26). Method 1. We can take the reciprocal of (2):
Method 2. Let where and , i.e.
What we want is in terms of , so our strategy is to express in terms of using trigonometric identities.
View On WordPress
0 notes
Compositions of trigonometric and inverse trigonometric functions (25)
Compositions of trigonometric and inverse trigonometric functions (25)
Proof of (25). Method 1. We can take the reciprocal of (1):
Method 2. Let where and , i.e.
What we want is in terms of , so our strategy is to express in terms of using trigonometric identities.
View On WordPress
0 notes