Question 1054984
<pre><font size=4><b>Geometric series:
__ + __ + 63 + __ + 567 + ___ + ___ + ___ = ???
</font>
{{{matrix(16,1,

matrix(1,3,63*r,""="",a[4]),

matrix(1,3,(63*r)*r,""="",567),

matrix(1,3,63*r^2,""="",567),

matrix(1,3,r^2,""="",9),

matrix(1,3,r,""="","" +- 3),

matrix(1,3,63*("" +- "3`"),""="",a[4]),

matrix(1,3,189,""="",a[4]),

matrix(1,7,a[2],""="",a[3]/r,""="",63/("" +- 3),""="","" +- 21),

matrix(1,7,a[1],""="",a[2]/r,""="",("" +- 21)/("" +- 3),""="",7),

matrix(1,7,a[6],""="",a[5]*r,""="",567*("" +- "3`"),""="","" +- 1701),

matrix(1,7,a[7],""="",a[6]*r,""="",("" +- 1701)*("" +- "3`"),""="",5103),

a[1]+a[2]+a[3]+a[4]+a[5]+a[6]+a[7],
""="",
7+21+63+189+567+1701+5103=7651,
or,
7-21+63-189+567-1701+5103=3829



)}}}

Edwin</pre></b>