So basically the question wants to confuse by saying “6 months” which is half a year, right? Do everything normally until 4yrs and then write into compound interest formula but with n as 1/2 which is root.
Let's use Pythagorean theorem.
![a^{2}+b^{2}=c^{2}](https://tex.z-dn.net/?f=a%5E%7B2%7D%2Bb%5E%7B2%7D%3Dc%5E%7B2%7D)
where
![c](https://tex.z-dn.net/?f=c)
is the hypotenuse.
So if we set it up:
![7^{2}+b^{2}=13^{2}](https://tex.z-dn.net/?f=7%5E%7B2%7D%2Bb%5E%7B2%7D%3D13%5E%7B2%7D)
now we simplify:
![49+b^{2}=169](https://tex.z-dn.net/?f=49%2Bb%5E%7B2%7D%3D169)
and get
![b^{2}](https://tex.z-dn.net/?f=b%5E%7B2%7D)
by itself:
![b^{2}=120](https://tex.z-dn.net/?f=b%5E%7B2%7D%3D120)
Now to get
![b](https://tex.z-dn.net/?f=b)
by itself, we need to take the square root of both sides:
![b=\sqrt{120}](https://tex.z-dn.net/?f=b%3D%5Csqrt%7B120%7D)
And that's your answer!
When there are more the one values on right side for any value on left side , then it is not a function .
In the given figure as all the values on left side have single and unique answers on the right side ,
So yes V(x) is function.
TRUE