Aquadratic pattern has a second term equal to 1,a third term equal to -16 and a fifth term equal to -14
1.1.1.calculate the second difference of this quadratic pattern
1.1.2.hence or otherwise, calculate the first term of term

Given are several terms in a quadratic pattern:

a1 = ?
a2 = 1
a3 = -16
a4 = ?
a5 = -14

let:

x       y
1       ?
2       1
3      -16
4       ?
5       -14

considering the 2nd term and 3rd term, we can determine a quadratic function:

y = -17x + 35

therefore,

a1 = 18
a4 = -33