The first polynomial is 2x & sup2; - 2XY + 3Y, the second one is less than 2 times of the first one by 1, and the third one is multinomial The first polynomial is 2x & sup2; - 2XY + 3Y, the second polynomial is less than 2 times of the first polynomial by 1, and the third polynomial is the sum of the first two polynomials. Find the sum of the three polynomials.
The second is 2 (2x & sup2; - 2XY + 3Y) - 1 = 4x & sup2; - 4xy + 6y-1, so the third is (2x & sup2; - 2XY + 3Y) + (4x & sup2; - 4xy + 6y-1) = 2x & sup2; - 2XY + 3Y + 4x & sup2; - 4xy + 6y-1 = 6x & sup2; - 6xy + 9y-1, so sum = 2 × the third = 2 (6x & sup2; - 6xy + 9y-1) = 12x & sup2; - 12xy