N =(18n² 9n 8)/n, where n belongs to integer. How many integral soluti...
Solution:
Given expression is N =(18n² + 9n + 8)/n
To find out the integral solutions of N, we need to find the values of n which make the expression an integer.
Let us try to simplify the expression to identify the factors of N.
N = (18n² + 9n + 8)/n
= 18n + 9 + 8/n
= 18n + (8/n) + 9
Now, we can see that N will be an integer if and only if 8/n is an integer.
This is because 18n and 9 are always integers and their sum will also be an integer.
Therefore, we need to find the factors of 8 which are integers.
Factors of 8 are ±1, ±2, ±4, and ±8.
So, the possible values of n are ±1, ±2, ±4, and ±8.
Let us substitute each of these values of n in the expression for N and check whether it is an integer or not.
When n = 1, N = (18 + 9 + 8)/1 = 35, which is an integer.
When n = -1, N = (-18 - 9 + 8)/(-1) = 35, which is an integer.
When n = 2, N = (72 + 18 + 8)/2 = 49, which is an integer.
When n = -2, N = (-72 - 18 + 8)/(-2) = 49, which is an integer.
When n = 4, N = (288 + 36 + 8)/4 = 83, which is an integer.
When n = -4, N = (-288 - 36 + 8)/(-4) = 83, which is an integer.
When n = 8, N = (1296 + 72 + 8)/8 = 170, which is an integer.
When n = -8, N = (-1296 - 72 + 8)/(-8) = 170, which is an integer.
Therefore, there are 8 integral solutions of N possible, which are 35, 35, 49, 49, 83, 83, 170, and 170.
N =(18n² 9n 8)/n, where n belongs to integer. How many integral soluti...
hey this d=sol is given by edurev study material however I also don't understand the solution
The given expression can be broken as: 18n2/n + 9n/n + 8/n. This gives us: 18n + 9 + 8/n.
- Now we can see that whatever the value of ‘n’, 18n + 9 will always give an integral value. Therefore, it now depends upon 8/n only ⇒ n can have any integral value, which is a factor of 8.
- The integers, which will satisfy this condition are �1, �2, �8, �4. Thus, in total, n can take 8 values.
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