Practicing Success
If x4 + x-4 = 194, x > 0 Find (x - 2)2. |
1 2 -3 3 |
3 |
Formula → x4 + \(\frac{1}{x^4}\) = a → x2 + \(\frac{1}{x^2}\) = \(\sqrt {a + 2}\)
x4 + \(\frac{1}{x^4}\) = 194 x2 + \(\frac{1}{x^2}\) = \(\sqrt {194 + 2}\) = 14 x + \(\frac{1}{x}\) = \(\sqrt {14 + 2}\) = 4 x2 + 1 = 4x x2 - 4x = -1 Now, we have to find (x - 2)2 x2 - 4x + 4 = -1 + 4 = 3 |