Coefficient

　　A constant multiplier of a variable is known as coefficient. They are typically represented by letters a,b,c.

　　Example:

　　In the expression 3x+5,3 is the coefficient of x.

　　In the equation 4x+2y=6,4 is the coefficient of x and 2 is the coefficient of y.

　　In the inequality 2*sin(x)+3>z,2 is the coefficient of the function sin(x).

　　Remember:

　　Coefficient cannot change its value.

　　GRE數學考點介紹：Multiplying Monomials

　　Multiplying Monomials

　　To multiply two monomials, multiply the coefficients and add the power of the variables.

　　By multiplying 3x and 4x, we get (4*3)x∧(1+1)=12x2.

　　By multiply 3x and 4y, we get (4*3)xy=12xy.

　　Remember:

　　Do not forget to add the powers of the same variable.

　　The terms need not be like terms to be multiplied.