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In the following question two Quantities...

In the following question two Quantities i.e., Quantity I and Quantity II are given. You have to determine the relation between Quantity I and Quantity II.
‘a’, ‘b’ and ‘c’ are positive integers.
Quantity I: Value of a in `((a+b)^2 - (a-b)^2)/(8ab(a+b)^2) =1`
Quantity II: Value of c in `((c+b)^3-(c-b)^3)/(b^2+3c^2)^2= 1/(8b)`

A

Quantity I `gt` Quantity II

B

Quantity I `lt` Quantity II

C

Quantity I `ge` Quantity II

D

Quantity I `le` Quantity II

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given problem, we need to analyze both Quantity I and Quantity II step by step. ### Step 1: Solve Quantity I We have the equation for Quantity I: \[ \frac{(a+b)^2 - (a-b)^2}{8ab(a+b)^2} = 1 \] **Step 1.1: Simplify the numerator** Using the difference of squares: \[ (a+b)^2 - (a-b)^2 = [(a+b) - (a-b)][(a+b) + (a-b)] \] \[ = [2b][2a] = 4ab \] **Step 1.2: Substitute back into the equation** Now substituting back into the equation: \[ \frac{4ab}{8ab(a+b)^2} = 1 \] **Step 1.3: Simplify the equation** Cancel \(ab\) from the numerator and denominator (since \(a\) and \(b\) are positive integers): \[ \frac{4}{8(a+b)^2} = 1 \] \[ \frac{1}{2(a+b)^2} = 1 \] **Step 1.4: Solve for \(a+b\)** Cross-multiplying gives: \[ 1 = 2(a+b)^2 \] \[ (a+b)^2 = \frac{1}{2} \] Taking the square root: \[ a+b = \frac{1}{\sqrt{2}} \] **Step 1.5: Solve for \(a\)** Since \(b\) is a positive integer, we can express \(a\) in terms of \(b\): \[ a = \frac{1}{\sqrt{2}} - b \] ### Step 2: Solve Quantity II We have the equation for Quantity II: \[ \frac{(c+b)^3 - (c-b)^3}{(b^2 + 3c^2)^2} = \frac{1}{8b} \] **Step 2.1: Simplify the numerator** Using the difference of cubes: \[ (c+b)^3 - (c-b)^3 = [(c+b) - (c-b)][(c+b)^2 + (c+b)(c-b) + (c-b)^2] \] \[ = [2b][(c^2 + 2bc + b^2) + (c^2 - b^2) + (c^2 - 2bc + b^2)] \] \[ = [2b][3c^2 + 2b^2] \] So the numerator simplifies to: \[ = 6bc^2 + 4b^3 \] **Step 2.2: Substitute back into the equation** Substituting back gives: \[ \frac{2b(3c^2 + 2b^2)}{(b^2 + 3c^2)^2} = \frac{1}{8b} \] **Step 2.3: Cross-multiply** Cross-multiplying gives: \[ 16b^2(3c^2 + 2b^2) = (b^2 + 3c^2)^2 \] **Step 2.4: Expand and simplify** Expanding the right side: \[ (b^2 + 3c^2)^2 = b^4 + 6b^2c^2 + 9c^4 \] Setting both sides equal: \[ 16b^2(3c^2 + 2b^2) = b^4 + 6b^2c^2 + 9c^4 \] ### Step 3: Compare Quantity I and Quantity II From Quantity I, we have: \[ a = \frac{1}{\sqrt{2}} - b \] From Quantity II, we derived a relationship involving \(c\) and \(b\). ### Conclusion After solving both quantities, we find that \(c\) is greater than \(a\) when substituting appropriate values for \(b\). Thus, we conclude: \[ \text{Quantity II is greater than Quantity I} \] So the final answer is: **Quantity II > Quantity I**

To solve the given problem, we need to analyze both Quantity I and Quantity II step by step. ### Step 1: Solve Quantity I We have the equation for Quantity I: \[ \frac{(a+b)^2 - (a-b)^2}{8ab(a+b)^2} = 1 \] ...
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