Week 4 – Precalc 11

In the blink of an eye, we have completed one month of the new school year. In Week 4, we focused on Chapter 2.3, “Multiplying and Dividing Radical Expressions.” In order to multiply or divide radical expressions, the radicand cannot be negative. Once the value has been confirmed, one can use the distributive property to expand the expression. It is important to remember to multiply first before doing the addition. For example, in Question 8c:

In Question 10b, we try to find the conjugate of a binomial expression. To do so, we need to multiply the whole fraction by the conjugate of the denominator. As shown below, the conjugate of – is +.

As seen above, once the denominator has been conjugated, we must use FOIL and BEDMAS to expand the expression. It is important to find identical radicals and pay attention to the symbols during the operation.

One thing I practiced on this week was to simplify radicals with variable radicands. In simplifying , must be broken down to its squarable factors. For this reason, 12 becomes 4 and 3. Since the square root of 4 is 2, becomes 2 . can further be simplified as follows. For comparison purpose, the calculation for is also shown.