Question
Prove that $\sqrt{3}+\sqrt{2}$ is irrational.

Answer

Let $\sqrt{3}$ is a rational number.
So, two integers $a$ and $b$ can be found so that $\sqrt{3}=\frac{a}{b}$Assume that a and are co$-$prime.
$\Rightarrow a=\sqrt{3} b$
Squaring both the sides,
$\Rightarrow a^2=3 b^2$
So, $a^2$ is divisible by $3$ and it can be said that a is divisible by $3 .$
Let $a^2=3 c$, where $c$ is an integer.
$a^2=3 b^2$
$\Rightarrow(3 c)^2=3 b^2 \Rightarrow b^2=3 c^2$
So, $b^2$ is divisible by $3$ and it can be said that $b$ is divisible by $3 .$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

To warm ships for underwater rocks, a lighthouse spreads a red coloured light over a sector of angle 80° to a distance of 16.5 km. Find the area of the sea over which the ships are warned.(use $\pi=3.14$ )
250 lottery tickets were sold and there are 5 prizes on these tickets. If kunal has purchased one lottery ticket, what is the probability that he wins a prize?
Solve the following quadratic equation:(2x - 3)(3x + 1) = 0
A small terrace at a football ground comprises of 15 steps each of which is 50 m long and built of solid concrete.
Each step has a rise of $\frac{1}{4}$m and a tread of $\frac{1}{2}$m. (see figure). Calculate the total volume of concrete required to build the terrace.
[Hint: Volume of concrete required to build the first step = $\frac 14 \times \frac 12 \times$ 50 $m^3$]
Find the mean of the following frequency distribution using step-deviation method:
Class
84-90
90-96
96-102
102-108
108-114
114-120
Frequency
15
22
20
18
20
25
Two coins are tossed simultaneously. What is the probability of getting at least one head?
The area of a circular playground is $22176 m^2$. Find the cost of fencing this ground at the rate of ₹ 50 per metre.
A data has 25 observations arranged in a descending order. Which observation represents the median?
A game consists of tossing a one-rupes coin three times, and noting its outcome each time. Find the probability of getting.
  1. Three heads.
  2. At least 2 tails.
How many multiples of $4$ lie between $10$ and $205$ ?