Start by looking at the leading terms. The divisor's 2x goes into the dividend 6x^3 a 3x^2 number of times. Multiply this by the divisor and you get 6x^3+3x^2. Subtract from the dividend and get -4x^2. 2x goes into this -2x times. Multiply by the divisor and get -4x^2 - 2x. Subtract and get 2x. Bring down the 1 term yielding 2x+1. 2x+1 goes into 2x+1 only 1 time. Thus the quotient is 3x^2-2x+1 which is option b.
