(a) Write the sum
1 β
1
5
+
1
25
β
1
125
+
1
625
β
1
3125
+
1
15625
β
1
78125
+
1
390625
in summation notation over the range of summation the integer interval [2..10]. That
is, find an expression ak so that
X
10
k=2
ak
is equal to the given sum.
(b) Using your expression from part (a), consider the summation obtained by taking
the absolute value of each term:
X
10
k=2
|ak|
Express this summation as the summation of a finite difference.
Hint: Use one of the 3 examples we discussed in class.
(c) Shift the index in your summation from part (b) so that the summation starts at
k = 0 and determine the value of the summation without the use of a calculator!
That is, use the formula for telescoping summation, linearity of summation and a formula we discussed in class
(10. in the figure, a aabc is drawn tocircumscribe a circle of radius 3 cm ,such thatthe segments bd and dc are respectively oflength 6 cm and 9 cm. find the length ofsides ab and ac.