Which of the following shows that the sum of two irrational numbers can be irrational?

A. (5+π)+(3-π)

B. √3+√5

C. (3+√5)+(3-√5)

D. (π/3)+(-π/3)

help?

Respuesta :

Given:

The sum of irrational number in the options.

To find:

The option that shows the sum of two irrational numbers can be irrational.

Solution:

In option A,

[tex](5+\pi)+(3-\pi)=5+\pi+3-\pi[/tex]

[tex](5+\pi)+(3-\pi)=5+3[/tex]

[tex](5+\pi)+(3-\pi)=8[/tex]

We know that 8 is a rational number. So, option A is incorrect.

In option B,

[tex]\sqrt{3}+\sqrt{5}[/tex]

Here both numbers are irrational and it cannot be simplified further.

So, [tex]\sqrt{3}+\sqrt{5}[/tex] is an irrational number and option B is correct.

In option C,

[tex](3+\sqrt{5})+(3-\sqrt{5})=3+\sqrt{5}+3-\sqrt{5}[/tex]

[tex](3+\sqrt{5})+(3-\sqrt{5})=3+3[/tex]

[tex](3+\sqrt{5})+(3-\sqrt{5})=6[/tex]

We know that 6 is a rational number. So, option C is incorrect.

In option D,

[tex](\dfrac{\pi}{3})+(-\dfrac{\pi}{3})=\dfrac{\pi}{3}-\dfrac{\pi}{3}[/tex]

[tex](\dfrac{\pi}{3})+(-\dfrac{\pi}{3})=0[/tex]

We know that 0 is a rational number. So, option D is incorrect.

Therefore, the correct option is B.