Question

i want most important formula of maths for class10

Answer 1

Hey there!

$\underline {Class 10 CBSE Maths }$

$\textbf {2. Polynimials }$

1. if α and β are zeroes of a quadratic polynomial, then

$\alpha + \beta = \frac{ - b}{a}$

$\alpha \beta = \frac{c}{a}$

2. General form of a quadratic equation

$x {}^{2} + ( \alpha + \beta )x + ( \alpha \beta )$

$\textbf {3. Pair of Linear Equations in two variable. }$

1. Behaviour of lines representing a pair of Linear Equations in two variable and the existence of solutions

(i) The lines may intersect in a single point. (unique solution - consistent )

(ii) The lines maybe parallel. (no solutions- inconsistent)

(iii) The lines maybe coincident (infinitely many solutions - consistent)

2. Cross Multiplication Method

(Attachement 2)

3.
$\frac{x}{b1c2 - b2c1} = \frac{y}{c1a2 - c2a1} = \frac{1}{a1b2 - a2b1}$

$\textbf {3. Quadratic Equations . }$

1. Quadratic formula

(Attachment 1)

2. Discriminant

$b {}^{2} - 4ac$

$\textbf {4. Arithemetic Progression }$

1.
$an = a + (n - 1)d$

$2.s = \frac{n}{2} [2a + (n - 1)d]$

$3.s = \frac{n}{2} (a + l)$

$\textbf {7. Coordinate Goemetry . }$

1. Distance b/w P(x1, y1) and Q (x2, y2)

$\sqrt{(x2 - x1) {}^{2} + (y2 - y1) {}^{2} }$

2. Distance of a point P(x,y) from origin

$\sqrt{x {}^{2} + y {}^{2} }$

3. The coordinates of line segment joining P(x1,y1) and Q (x2,y2)

$( \frac{m1x2 + m2x1}{m1 + m2} \: \frac{m1y2 + m2y1}{m1 + m2})$

4. The mid-point of line segment joining points (x1, y1), (x2, y2) and (x3, y3) is numerical value of the expression.

$\frac{1}{2} [x1(y2 - y3) + x2(y3 - y1) + x3(y1 - y2)]$

$\textbf {8. Introduction to Trigonometry }$

SOH CAH TOA

(Attachment3)

$\textbf {12.Areas related to Circles. }$

1. Volume of frustum of cone
$\frac{1}{3} \pi \: h(r1 {}^{2} + r2 {}^{2} + r1r2)$

2. C.S.A of frustum of cone
$\pi \: l(r1 + r2)$
where
$l = \sqrt{h {}^{2} + (r1 - r2) {}^{2} }$

3. TSA of frustum of cone
$\pi \: l(r1 + r2) + \pi(r1 {}^{2} + r2 {}^{2} )$

$\textbf {14. Statistics }$

[Refer Attachement5]

$\textbf {15.Probability }$

1. P(E) = No.of outcomes fav. to E/No.of all possible outcomes of experiment

Hope it helps!!