Question

Show that 7+2√5 is an irrational number.​

Answer 1

Answer:

11.47213595

Step-by-step explanation:

2√5=4.47213595

so 7+2√5=7+4.47213595=11.47213595

2√5 is a irrational number so the sum of the 2√5 with a whole number will be irrational number.

Answer 2

Answer:

I hope my answer is helpful for you

Step-by-step explanation:

Let us assume to the contrary that 7-√5 is rational number

i.e,we can find co prime number a and b where b ≠0

such that :-

=>7-√5 = a/b

=>7 - a/b = √5

by rearranging this equation we get

=> √5 = 7 - a/b

=> √5b = 7b - a

since a and b are are irrational number