Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
6 Cards in this Set
- Front
- Back
|
When sum and difference of two numbers (X and Y) are given, then |
X = (sum + difference)/2 Y = (sum + difference)/2 |
|
|
Difference between two digits of two digit number is = |
(Difference in original and interchanged number)/9 |
|
|
Sum of first n odd numbers is |
n*2 |
|
|
Sum of first n even numbers is |
n(n+1) |
|
|
Sum of squares of first n natural numbers is |
n(n+1)(2n+1)/6 |
|
|
Sum of cubes of first n natural numbers is |
[n(n+1)/2]*2 |
