The number of solutions of 2 x + (2 + 2x - x2 ) x - 3(x - 1)2 = 0, where - x , is .
Answer
2
Solution
2 + 2x - x2 = 3 - (x - 1)2; let k = (x - 1)2:
2 x + (3 - k) x - 3k = 0 ( x + 3)( x - k) = 0
x -3 x = (x - 1)2
[figure]
(x - 1)2 0 only x [0, ] possible; x > 2 (x - 1)2 > 1 x
x = 0: 0 < 1; x = 1: 1 > 0; x = 2: 2 < 1 one crossing in (0, 1), one in (1, 2)
Answer: 2