Let f(x) = t2 – 15
Now, if we recall the identity
(a2 – b2) = (a – b)(a + b)
Using this identity, we can write
t2 – 15 = (t – √15) (x + √15)
So, the value of t2– 15 is zero when t = √15 or t = – √15
Therefore, the zeroes of t2– 15 are √15 and – √15.
Verification
Now,
So, the relationship between the zeroes and the coefficients is verified.