Definitions: Mathematics 11: PTB by Muzzammil Subhan

Definitions from Textbook of Algebra and Trigonometry Class XI, published by Punjab Textbook Board (PTB) Lahore, Pakistan. We are very thankful to Muzzammil Subhan for his valuable contribution. Download or view PDF for all definitions. Samples is given below

• Exponential Function: A function in which variable appear as power of a constant is called exponential Function. e.g. $y=2^x$, $y=e^x$
• Logarithmic Function: The functions $f(x)=\log_a x$ and $f(x)=\log_e x$ are called general and natural logarithmic function respectively.
• Explicit Function: If $y$ is easily expressed in term of $x$ then $y$ is called an explicit function. E.g. $y=x^2+3x$
• Implicit Function: If y is not expressed in term of x then y is called an implicit function. E.g. $x^2+xy+y^2=4$
• Even Function: A function is said to be an even function if $f(-x)=f(x)$
• Odd Function: A function is said to be an odd function if $f(-x)=-f(x)$
• Circle: “A set of all points in a plane which are equidistant from a fixed point is called circle.” The fixed point is called centre and fixed distance is called radius of circle.
• Point Circle: A circle whose radius is zero is called point circle.
• Parabola: “A set of all points in a plane which are equidistant from fixed point and fixed line.” The fixed point is called focus and fixed line is called directrix of parabola.
• Ellipse: A set of all points in a plane such that distance of each point from a fixed point bear a constant ratio less then one to the distance from a fixed line.
• Hyperbola: A set of all points in a plane such that distance of each point from a fixed point bear a constant ratio greater then one to the distance from a fixed line.