i am so lost on this please explain?

Question

I have to Simplify
sqrt 20 div by 5 - 1/sqrt 5

Answer 1

√20/5 -1/√5
√20=√(4*5)=2√5
2√5/5 -1/√5
=2/√5 -1/√5
=1/√5 *(√5/√5)--(rationalize)
=√5/5

Answer 2

step 1: put it all over a common factor
to do this you have to multiply 1/sqrt(5) top and bottom by sqrt(5) to give:
sqrt(5) / 5

then you can add the terms together to get
[sqrt(20) - sqrt(5)] / 5

Step 2: expand and simplify the numerator
sqrt(20) = sqrt(4) x sqrt(5)
= 2 x sqrt(5)

so now we have [2 x sqrt(5) - sqrt(5)] / 5
= sqrt(5) / 5

Step3: cancel down the fraction
5 = sqrt(5) x sqrt(5)
so we get
sqrt(5) / [sqrt(5) x sqrt(5)]
= 1 / sqrt(5)

so your answer is
sqrt(5) / 5 or 1 / sqrt(5)
depending on whether you want a rational denominator

Answer 3

I assume this is (sqrt20/5) -1/sqrt(5)

put over a common denominator by cross multiplying:

(sqrt20(sqrt(5) -5)/ 5sqrt(5)
you can factor sqrt5 from first term:

((sqrt(4)sqrt(5)(sqrt(5) -5)/5sqrt5

now substitute 2 for the sqrt 4 and 5 for sqrt(5)(sqrt(5):

(2(5) -5)/5sqrt5 = 1/sqrt(5)

Answer 4

You have to multiply the second section section by (sqrt5)/(sqrt5). That's the way to get rid of sqrt in denominator. So that will be (1/sqrt5)*(sqrt5/sqrt5). 1*sqrt5 = sqrt 5, and sqrt5*sqrt5 = 5.

So now you have (sqrt20)/5 - (sqrt5/5). Sqrt20 can be factored down to (2*sqrt5). Then just add 2*sqrt5 + sqrt5 = 3*sqrt5. Divide that by the 5 on the bottom.

Final answer is (3*sqrt5)/(5)

Answer 5

The problem is not well defined.

[(20/5)^0.5 - 1] / 5^0.5 is one way of writing what you wrote.

That would be 4^0.5 - 1 = 3-1 = 2 divided by sqrt.5
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But if we write (sqrt.20 / 5) - (1/sqrt.5) we can write it as:

sqrt.20 = sqrt. 4X5 = 2 sqrt.5 and this divided by 5 gives
2/sqrt.5 and then we have
2/sqrt.5 - 1/sqrt.5 = 1/sqrt.5

This appears to be more reasonable.

Answer 6

sqrt(20)/5-1/sqrt(5)
=sqrt(20/25)-1/sqrt(5)
=sqrt(4/5)-1/sqrt(5)
=sqrt(4)/sqrt(5)-1/sqrt(5)
=2-1/sqrt(5)
=1/sqrt(5)
that is approximately equal to 0.447215

Answer 7

√20/5 - 1/√5
= √(4 x 5) / 5 - √5 / 5
= 2.√5 / 5 - √5 / 5
= (1/5).(2√5 - V5)
= (1/5).√5

Answer 8

sqrt20/(5 -1/sqrt5) = sqrt 20 sqrt5/(sqrt5 - 1) = sqrt100/(sqrt5 - 1) = 10/ (sqrt5 - 1) = 5/2 (sqrt5 +1)