180 likes | 581 Views
Dividing Radicals. Dividing Radicals – the Basics. Like with multiplying radicals, to divide radicals they must have the same INDEX . Remember, division is often written as a fraction .
E N D
Dividing Radicals – the Basics • Like with multiplying radicals, to divide radicals they must have the same INDEX. • Remember, division is often written as a fraction. • As with multiplying radicals, you can divide/reduce the coefficients to get the coefficient of the quotient, then divide/reduce the radicand to get the radicand of the quotient. • The final basic fact you need to know is: to take the root of a fraction, you take the root of both the numerator and denominator. • Lets try some examples…
Divide num. & denom. by 3 Divide num. & denom. by 2 Divide num. & denom. by 25 • Are the indices the same? • YEP!!! Let’s do this! • Divide/reduce the coefficients and radicands. • Simplify your radical • Are the indices the same? • YEP!!! Let’s do this! • Divide/reduce the coefficients and radicands. • Simplify your radical. What happened to the denominator? Final check: are your radical and fraction completely simplified?
How do you divide powers? • How do I take the square root of a fraction? • Take the square root of the numerator and denominator separately. But make your life easier – simplify your fraction first. • Now split it up and simplify. • Since the radicand is a fraction, simplify the fraction first. • Take the root of the denom. and numerator separately. • Simplify. Divide num. & denom. by 3 Divide num. & denom. by 7 Where does the -6 go?? Nope, we’re not done yet. One more small step for man, one giant leap for fraction kind..
One of those really important math rules…. • You know you need to simplify fractions completely, combine like terms, simplify radicand, etc. before you can say you have ‘finished’ a problem. • One other rule you need to know is that you NEVER leave a radical in the denominator of a fraction! • We will use our knowledge of simplifying radicals and of equivalent fractions to make sure we don’t break this rule!
Rationalizing Denominators Final check: are your radical and fraction completely simplified? Step 1 – simplify our fraction Step 2 – simplify our radicands Step 3– rationalize the denominator Why do we still have a radical in the denominator? What would we need for the radical to simplify?
Rationalizing Denominators Final check: are your radical and fraction completely simplified? Step 1 – simplify the fraction Step 2 – split it up and simplify the radicands Step 3– rationalize the denominator Why do we still have a radical in the denominator? What would we need for the radical to simplify?