# Math Formulas for Class 11

It’s quite common amongst students to find math as a difficult subject and find it hard to master. Many students of CBSE class 11 are phobic about math formulas, because of their negativity towards the subject and cannot focus or concentrate on math problems. Students have the most trouble before exams or even small class tests; that’s when nervousness kicks in. Due to the negativity and resentment towards math, most students fail their exams.

The only way students can get rid of the subject is by learning to get a strong grip on maths formula. If students can do their best to be positive about maths formula they can achieve the kind of marks they desire. All those students need to do is to understand the concepts learn all the necessary math formulas and apply these formulas according to the problem and find the solution to a difficult question.

Here is a list of Maths formulas for CBSE class 11.

Coordinate Geometry & Line Formula

 Coordinate Geometry & Lines Formulas for Class 11 Distance Formula $\left | P_{1}P_{2} \right |=\sqrt{\left ( x_{2}-x_{1} \right )^{2}+\left ( y_{2}-y_{1} \right )^{2}}$ Slope $\large m=\frac{rise}{run}=\frac{\Delta y}{\Delta x}=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$ Point-Slope Form $y-y_{1}=m\left ( x-x_{1} \right )$ Point-Point Form $y-y_{1}=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}\left ( x-x_{1} \right )$ Slope-Intercept Form $y=mx+b$ Intercept-Intercept Form $\frac{x}{a}+\frac{y}{b}=1$ General Form $Ax+By+C=0$ Parallel & Perpendicular Lines Parallel Lines $m_{1}=m_{2}$ Perpendicular Lines $m_{1}m_{2}=-1$ Distance from a Point to a Line $\large d=\frac{\left | Ax_{0}+By_{0}+C \right |}{\sqrt{A^{2}+B^{2}}}$

Algebra Formula-

 Algebra Formulas For Class 11 Distributive Property $a\, \left ( b+c \right ) = a \times b\, +\, a \times c$ Commutative Property of Addition $a\, +\, b\, =\, b\, +\, a$ Commutative Property of Multiplication $a\,\times b\, =\, b\,\times a$ Associative Property of Addition $a\, +\, \left ( b\, +\, c \right ) = \left ( a\, +\, b \right )\, +\, c$ Associative Property of Multiplication $a\,\times \left ( b\,\times c \right ) = \left ( a\,\times b \right )\,\times c$ Additive Identity Property $a\, +\, 0\, =\, a$ Multiplicative Identity Property $a\, \times 1\, =\, a$ Additive Inverse Property $a\,+\left ( -a \right )=0$ Multiplicative Inverse Property $a \cdot \left ( \frac{1}{a} \right )=1$ Zero Property of Multiplication $a\times \left ( 0\right )=0$

Trigonometric Formula-

 Trigonometry Class 11 Formulas $\sin (-\theta ) = -\sin \theta$ $\cos (-\theta ) = \cos \theta$ $\tan (-\theta ) = -\tan \theta$ $cosec (-\theta ) = -cosec \theta$ $\sec (-\theta ) = \sec \theta$ $\cot (-\theta ) = -\cot \theta$ Product to Sum Formulas $\sin \, x \,\ sin \, y = \frac{1}{2}\left [ \cos\left ( x – y \right ) -\cos \left ( x+y \right ) \right ]$ $\cos\, x \, \cos\, y = \frac{1}{2}\left [ \cos \left ( x – y \right ) + \cos \left ( x+y \right ) \right ]$ $\sin\, x \, \cos\, y = \frac{1}{2}\left [ \sin\left ( x + y \right ) + \sin \left ( x-y \right ) \right ]$ $\cos\, x \, \sin\, y = \frac{1}{2}\left [ \sin\left ( x + y \right ) – \sin\left ( x-y \right ) \right ]$ Sum to Product Formulas $\sin\, x + \sin \, y = 2\, \sin \left ( \frac{x+y}{2} \right ) \cos \left ( \frac{x-y}{2} \right )$ $\sin\, x -\sin\, y = 2\, \cos \left ( \frac{x+y}{2} \right ) \sin \left ( \frac{x-y}{2} \right )$ $\cos \, x + \cos \, y = 2 \, \cos \left ( \frac{x+y}{2} \right ) \cos\left ( \frac{x-y}{2} \right )$ $\cos\, x -\cos\, y = – 2 \, \sin \left ( \frac{x+y}{2} \right ) \sin \left ( \frac{x-y}{2} \right )$

#### Practise This Question

Which of the following functions are identical to f(x)  =
f(x)={x,1x<2x2,2x<3

(1 x < 3)