Question

Спростіть вираз (3x - y) (3x+y) + y²

Answer 1

$(3x - y)(3x + y) + {y}^{2} = \\ = 9 {x}^{2} - {y}^{2} + {y}^{2} = \\ = {9x}^{2}$

Answer 2

$(3x - y)(3x + y) + {y}^{2} = 9x {}^{2} - y {}^{2} + {y}^{2} = 9 {x}^{2}$