Your Practice Paper – Applications and Interpretation HL for IBDP Mathematics
19 Differentiation
dy
� � f�( x) : Derivative of the function y � f ( x)
( First derivative ) dx
� Rules of differentiation : 1 . n f ( x) � x � f �( x)
� nx �
n 1
2 . |
f ( x)
� p( x)
� q( x)
� f
�( x)
� p�( x)
� q�( x)
|
3 . |
f ( x)
�cp( x)
� f
�( x)
� cp�( x)
|
� Relationship between graph properties and the derivatives : 1 . f�( x) � 0 for a �x � b : f( x ) is increasing in the interval 2 . f�( x) � 0 for a �x � b : f( x ) is decreasing in the interval 3 . f�( a) � 0: ( a, f ( a )) is a stationary point of f( x ) 4 . f�( a) � 0 and f� ( x) changes from positive to negative at x� a: ( a, f ( a )) is a maximum point of f( x )
5 . f�( a) � 0 and f� ( x) changes from negative to positive at x� a: ( a, f ( a )) is a minimum point of f( x )
� Tangents and normals : 1 . f� ( a)
: Slope of tangent at x� a
2 .
�1 f�( a)
: Slope of normal at x� a
3 . y � f ( a) � f �( a)( x � a) : Equation of tangent at x� a
4 . y f 1 ( a � � �
� ) � � ( ) f ( a) x � �
� a � �
� Derivatives of a function y � f ( x)
:
1 .
2 .
2 d y d �d �
2 � d d d
y�
�� x x � x � n d y n dx
: Equation of normal at x� a f��( x) : Second derivative
( n) � f ( x)
: n -th derivative
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