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jQuery Practical - Fundamental-I

jQuery Practical - Fundamental-I

  1. Using jQuery find all textareas, and makes a border. Then adds all paragraphs to the jQuery object to set their borders red. Go to the editor You can see the output from

    .addBorder {
       border: 2px solid red;
}

$("#button1").on("click",function() {
    if ($("textarea").hasClass("addBorder")) {
        $("textarea").removeClass("addBorder");
    } else {
        $("textarea").addClass("addBorder");
    } 
});

  2. Set the background color red of the following elements using jQuery

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数的定义

数的定义

数定义WIKI
IntegerAn integer (from the Latin integer meaning "whole")[note 1] is a number that can be written without a fractional component.Integer
Postive NumberA number is positive if it is greater than zero.Sign (mathematics)
real numbera value that represents a quantity along a lineReal Number
Negative numbera negative number is a real number that is less than zero.Negative number
Rational NumberIn mathematics, a rational number is any number that can be expressed as the quotient or fraction p/q of two integers, a numerator p and a non-zero denominator q.Reational number
Irrational numberirrational number is a real number that cannot be expressed as a ratio of integers, i.e. as a fraction.Irrational number
LogarithmIn mathematics, the logarithm is the inverse operation to exponentiation.Logarithm

  1. The rational numbers (ℚ) are included in the real numbers, and in turn include the integers (ℤ), which include the natural numbers (ℕ)

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