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How do you simplify #3sqrt20 + 2sqrt45#?

Answer 1

#12sqrt5#

In most questions involving powers and roots, a good strategy is to break numbers down into their prime factors. This tells us what we are working with.

#3sqrt(4xx5) + 2 sqrt(9xx5)#

4 and 9 are square numbers, they have exact square roots.

= #3xx2sqrt(5) + 2xx3 sqrt(5)#

= #6sqrt(5) + 6sqrt(5)#

= #12sqrt5#

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Answer 2

Eva Adamson

To simplify 3√20 + 2√45, we can simplify the square roots of 20 and 45. The square root of 20 can be simplified to 2√5, and the square root of 45 can be simplified to 3√5. Therefore, the expression simplifies to 3√5 + 2√5, which can be further simplified to (3 + 2)√5, resulting in 5√5.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.