а) (у^2 - 2а) (2а + у^2) = 2ау^2 + у^4 - 4а^2 - 2ау^2 = у^4 - 4а^2
б) (3x^2 + x)^2 = (3x^2 + x)(3x^2 + x) = 9x^4 + 3x^3 + 3x^3 + x^2 = 9x^4 + 6x^3 + x^2
в) (2 + t)^2 (2 - t)^2 = (4 + 4t + t^2)(4 - 4t + t^2) = 16 - 16t^2 + t^4 = t^4 - 16t^2 + 16
а) (у^2 - 2а) (2а + у^2) = 2ау^2 + у^4 - 4а^2 - 2ау^2 = у^4 - 4а^2
б) (3x^2 + x)^2 = (3x^2 + x)(3x^2 + x) = 9x^4 + 3x^3 + 3x^3 + x^2 = 9x^4 + 6x^3 + x^2
в) (2 + t)^2 (2 - t)^2 = (4 + 4t + t^2)(4 - 4t + t^2) = 16 - 16t^2 + t^4 = t^4 - 16t^2 + 16