Question

Solve this ==>
Find the value of ==>
$\sqrt1 + 3 + 5 + 7 + ... + 19$
​

Answer 1

√1=1

so the question becomes

1+3+5+...+19

we see that its in AP

therefore we can apply the formula

a=1

d=2

an=a+(n-1)d

19=1+(n-1)2

18/2=(n-1)

n=10

n=10

Sn=n/2*(2a+(n-1)d)

=10/2*(2+9*2)

=5*20

=100

Hope this helps

Answer 2

Answer:

Refer to the Attachment dear.

$\:$

Legend Akhil