Determine which recurrence relation has the characteristic equation r2+2r+1=0r^2 + 2r + 1 = 0r2+2r+1=0.
an=−2an−1−an−2a_n = -2a_{n-1} - a_{n-2}an=−2an−1−an−2
an=2an−1+an−2a_n = 2a_{n-1} + a_{n-2}an=2an−1+an−2
an=an−1+2an−2a_n = a_{n-1} + 2a_{n-2}an=an−1+2an−2
an=−an−1−2an−2a_n = -a_{n-1} - 2a_{n-2}an=−an−1−2an−2