CH # 1 - Functions and Limits: 2 Year Mathematics
CH # 1 - Functions and Limits: 2 Year Mathematics
CH # 1 - Functions and Limits: 2 Year Mathematics
√ + −√ 1
25 lim =
→ 2√
Limit at Infinity
lim =0 lim =0
→ →
26 where ≠ 0 and ‘a’ is real number and ‘p’ is 27 where ≠ 0 and ‘a’ is real number and ‘p’
a positive rational number. is a positive rational number.
1
28 lim 1 + = 29 lim(1 + ) =
→ →
− −
30 lim = = ln 31 lim = = ln = 1
→ →
lim ( )=∞ 1
32 →
33 lim ( ) = lim =0
→ →
lim =0 lim =1
34 →± 35 →
Where ‘a’ is any real number. Where ‘ must be measured in radian
The Sandwitch Theorem
Let , ℎ be functions such that ( ) ≤ ( ) ≤ ( ) for all numbers ‘x’ in some open
36 interval containing ‘c’, except possibly at ‘c’ itself.
lim ( ) = and lim ℎ( ) = then lim ( ) =
→ → →
Continuous and Discontinuous Functions
Criterion for Existence of Limit of a Function
By using given blow procedure we can check existence of limit if any function:
If lim ( )
→
The Left hand Limit The Right hand Limit
37
lim ( )= lim ( )=
→ →
Then the functions will be continuous if
lim ( ) = and lim ( ) = lim ( )=
→ → →
Continuity of a Function at a Number
For Continuous Function:
A function will continuous at a number ‘c’ if and only if the following three conditions are
satisfied:
38 (i) Value of the function = ( ) is defined.
(ii) Limit of the function = lim ( ) should be exist.
→
(iii) lim ( ) = ( )
→
Then function will be continuous otherwise the function will be Discontinuous function if one of
them condition does not fulfill.
Ch # 2_Differentiation
Derivative of a Function
The derivative of constant function is always
( + )− ( ) zero
1 = ( ) = lim 2
→
( )=0
Derivative of a Sum or Difference of
Power Rule Functions
3 4
( )= ( ± )= ( )± ( )
5 [ ( )] = [ ( )] ( ) 6 [ ( )] = ( )
Quotient Rule
Product Rule
7 8 ( ) ( ) ( )− ( ) ( )
[ ( ) × ( )] = ( )× ( ) =
( ) [ ( )]
Ab-initio Method, First Principles , differentiations by definition
Finding ( ) from Definition of Derivative
If f(x) is given and if ( ) exist then it can be find by following the given steps:
(i) Taking increment of f(x) as ( + )
(ii) Subtract ( ) ( + ) ( + )− ( )
(iii) Divided ( + ) − ( ) by on both side and simplify.
( ) ( )
9 (iv) Taking limit as → 0 on both side as lim →
Apply the limit and get ( ).
In some questions related to this method we will use Binomial Theorem for simplification.
That is, when n is negative integer or a fraction and | | < 1
( − 1) ( − 1)( − 2)
(1 + ) = 1 + + + −−−−−−−
2! 3!
14 ( )= . 15 ( )= .
16 ( )=− . 17 ( )=− .
18 ( )= . 19 ( )=− .
20 ( )= . 21 ( )= .
22 ( )=− . 23 ( )=− .
Derivatives of Inverse Trigonometric Functions
1 1
24 (sin )= 25 (cos )=−
√1 − √1 −
1 1
26 (tan )= 27 (cot )=−
1+ 1+
1 1
28 (sec )= 29 (csc )=−
√ −1 √ −1
Derivatives of Exponential Functions
30 ( )= ( ) 31 ( )= ( )
32 33 ( ) ( )
( )= ln = ( ) ln
Derivatives of Logarithmic Functions
1 1
34 (ln ) = ( ) 35 ( )= ( )
ln
Derivatives of Hyperbolic Functions
36 (sinh )= ℎ . 37 (cosh )= ℎ .
49 ( ) = (0) + (0)
+ (0) + (0) + ( ) (0) + − − − − − −
1! 2! 3! 4!
We put = 0 in Tailor Series Expansion to get Maclaurin Series Expansion.
Ch # 3_Integration
Note:
Integration (∫….) and differentiation ( ) are inverse operations of each other.
The inverse process of differentiation i.e; the process of finding such a function whose
derivative is given is called anti-differentiation or integration.
We add the ‘c’ arbitrary constant after integration which is known as constant of
integration.
Which function whose integration is taken is called integrand.
∫[ ( ) ± ( )] = ∫ ( ) ±
1 ( ) = ( ) + 2
∫ ( ) +c
Logarithmic Rules
( )
3 = ln + 4 = ln ( ) +
( )
5 = | + |+ 6 = +
+ ln
( )
7 ( ) 8
( ) = + = +
ln b ln
Power Rules
[ ( )]
9 ∫[ ( )] ( ) = + ( ≠ −1) 10 = + ≠ −1
+1
1 ( + )
11 ( + ) = ( + ) . = + ≠ −1
+1
Exponential Rules
12 = + 13 = +
( ) ( ) ( )
14 = +
For Anti-Derivatives Formulae
15 ( ) = + 16 =− +
= | |+
17 = + 18 or
= | |+
19 = | |+ 20 = | + |+
= | − |+
or
21 22 . = +
= +
2
23 . =− + 24 = +
25 =− +
26 = sin + 27 = sin +
√1 − √ −
28 = − cos + 29 = −cos +
√1 − √ −
1
30 = tan + 31 = tan +
1+ +
1 + 1 −
32 = + 33 = +
− 2 − − 2 +
1
34 = sec + 35 = sec +
√ −1 √ −
1
36 = −cot + 37 =− cot +
1+ +
1
38 = −csc + 39 =− csc +
√ −1 √ −
+√ + +√ −
= + = +
√ + √ −
40 or 41 or
= + + + = + − +
√ + √ −
√ −
42 − = + sin +
2 2
√+
43 + = + ln + + +
2 2
√ −
44 − = − ln + − +
2 2
Integration by Parts
. = − ( ).
Or
(1 ). (2 )
= (1 ). ( 2 )
− [ 1 .( 2 )]
Note:
Consider ‘u’ as a first function and ‘v’ as a second function to Solve such question and follow the
given below procedure carefully:
45 Choose a ‘u’ as a 1st function that gets simpler when you differentiate it.
Choose a ‘v’ as a 2nd function that gets simpler when you integrate it.
For the purpose of selection as a 1st and 2nd function, we use ‘LIATE Rule’ (this rule
proposed by Herbert Kasube of Bradley university) and LIATE stands for:
L: Logarithmic functions such as ln(x), log(x)
-1 -1 -1
I: Inverse trigonometric functions such as sin (x), cos (x), tan (x)
2 3
A: Algebraic functions such as x , x
T: Trigonometric functions such as sin(x), cos(x), tan (x)
x x
E: Exponential functions such as e , 3