math
posted by unknown on .
The 6th term of an arithmetic sequence is x while
the 11th is y find the 1st 2 terms

a+5d = x
a+10d = y
subtract them
5d = yx
d = (yx)/5
and
a + 5(yx)/5 = x
a + y  x = x
a = 2x  y
first two terms are:
t1 = 2xy
t2 = 2xy + (yx)/5 = (10x  5y + yx)/5
= (9x  6y)/5