Roots of a quadratic equation

The calculator calculates the weighted average of the ratings of the following items.              

Converter allows you to convert numbers between number bases - binary (binary), trójkowym, czwórkowym, Friday, szóstkowym, siódemkowym, octal (octal), dziewiątkowym, decimal (decymalnym) jedenastkowym, dwunastkowym, trzynastkowym, czternastkowym, piętnastkowym, hexadecimal (hex). Typed characters that are not numbers and the letters A, B, C, D, E, F are ignored.      

Calculator by entering an angle in degrees or radians calculated values ​​of the basic trigonometric functions.

Calculator allows you to calculate the probability of a given number of successes with a specified number of trials and probability of success.

Covariance is a measure of the covariance of two variables (X and Y). The calculator calculates the average for the sample and the covariance between variables. Sets of X and Y must be the same number.      

Checks the calculator is a large number of so-called gay (Happy Number). Number gay is a natural number is defined as follows: Calculate the sum of squares of digits of the number. Repeat this process for the next results as long as we get the number 1 or the results will be repeated. If you have received as a result of one, the original number is the number of gay. Otherwise, a number bleak.