Question

6. Evaluate the following expression: 1 + 3 + 5 + ... + 35 + 37.

Answer 1

(A) 361

(B) 362

(C) 324

(D) 323

Answer 2

this is an arithmetic progression [AP]

do u know how to calculate the summation of an AP?

Answer 3

not here rhett

Answer 4

ok sorry

Answer 5

e.e
its k

Answer 6

no i don't

Answer 7

ok theres a formula used to find the summation

Answer 8

do u remember any such formula?

Answer 9

something with n and +1 I'm not sure

Answer 10

ok the formula is this-
\[S=\frac{ n }{ 2 }\left( 2a+(n-1)d \right)\]
S=summation :) that is the sum
n=number of terms
a=1st term
d=common difference

:)

now your work is to find ->n,a,d
and then put them in this equation to get S

Answer 11

is there any other formula that's easier to remember

Answer 12

yes
u can also do it like this-
\[S=\frac{ n }{ 2 }(a+l)\]
here
S=summation
n=number of terms
a=1st term
l=last term

Answer 13

i got something different

Answer 14

what did u get?

Answer 15

703

Answer 16

which method did u choose?

Answer 17

2nd

Answer 18

ok what values of n,a,l did u get?

Answer 19

n=37
A=1
l=37

Answer 20

how did u get n=37 ?

Answer 21

cuz there are 37 terms right?

Answer 22

still there?

Answer 23

anyone?

Answer 24

Refer to the attachment created with the Mathematica computer program.

Answer 25

could you explain that