This week in pre-calc we finished up our roots and powers unit and started up our radical and operations unit, which is just growing off of what we did in our powers and roots unit as we are still using mixed and entire radicals and many other skills from that unit.
In this blog post I am going to explain how to add and subtract roots. I find this very similar to adding and subtract fractions, as when adding fractions you must have the same base, well in this case you must have the same radicand and just add the two coefficients.
Step 1: The first thing you’ll notice is that in this example the radicands aren’t the same. But I notice that they’re all perfect squares so I am going to pull out the perfect square and put it out front, now it is the coefficient.
Step 2: Now I notice all of my radicands are the same I am simply just going to add/subtract my coefficients. If this were a more complicated questions there could be some simplifying I have to do but in this example this is the final step.
Sometimes you have to put your radicand into a mixed radical to get the same radicand. I will show how to do that now.
In that example you can see I followed the same steps but I put them into mixed radicals. I then added the like ones and got my answer.
For adding and subtracting radicals you just have to remember to make them alike and if they can be alike then you just leave them.
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