If the difference between two numbers is 5 and the difference between the in cubes is 1850, then the difference between their squares is: |
$5\sqrt{484}$ $5\sqrt{482}$ $5\sqrt{485}$ $5\sqrt{483}$ |
$5\sqrt{485}$ |
Let the numbers be x and y According to the question, x - y = 5 x³ - y³ = 1850 We know that, (a - b)3 = a3 - b3 - 3ab(a-b) (5)3 = 1850 - 3ab(5) 125 = 1850 - 15ab 15ab = 1725 ab = 115 We also know that, If x - y = n then, x + y = \(\sqrt {n^2 + 4xy}\) then, x + y = \(\sqrt {5^2 + 4(115)}\) x + y = \(\sqrt {5^2 + 4(115)}\) x + y = \(\sqrt {485}\) The difference between their squares is = x2 - y2 = (x + y)(x - Y) = x2 - y2 = $5\sqrt{485}$ |