A new guideline for simplifying radicals is introduced: the terms in a fully-simplified radical expression must have no common radical factors. Simplifying a radical expression by adding or subtracting common radical factors is illustrated.
Simplifying a radical by multiplying first to get a perfect square in the radicand.
The process of simplifying to find a common radical factor is demonstrated.
Instances are demonstrated where simplifying radicals before multiplying are indicated.
This clip summarizes multiplication of whole numbers, including the relationship between addition and multiplication, the use of arrays, and the results when multiplying numbers by one or zero.
This clip explains that, just as zero is the identity for addition, the number 1 is the identity for multiplication because, any number, when multiplied by 1, "...isn't changed at all."
This clip explains that one way to look at multiplication is through a pattern of columns and rows known as an array.
This clip explains that the product of any number multiplied by zero is zero.
Illustrations of the rule for multiplying radicals: the square root of a times the square root of b equals the square root of the product a times b.
Rational expressions that equal -1 are recognizable: the terms in the numerator are identical to the terms in the denominator except for their signs, which are opposite.