Given that x=−1x = -1x=−1 and x=2x = 2x=2 are roots of P(x)=x3+ax2+bx+2P(x) = x^3 + ax^2 + bx + 2P(x)=x3+ax2+bx+2, which is true?
a=−1,b=−2a = -1, b = -2a=−1,b=−2
a=2,b=−1a = 2, b = -1a=2,b=−1
a=1,b=−1a = 1, b = -1a=1,b=−1
a=−2,b=−1a = -2, b = -1a=−2,b=−1