Question

if A=22.5 than (1+cosA)(1+cos3A)(1+cos5A)(1+cos7A)=?

Answer 1

no one replyyyyy?????

Answer 2

Are you alllowed to use a calculator

Answer 3

yes

Answer 4

bandar kya jane
jao madari ke paas

Answer 5

not yet

Answer 6

Where you are stuck

Answer 7

Reply

Answer 8

not yet

Answer 9

have you joined school-classXI

Answer 10

i am preparing for IIT , i am in 11th

Answer 11

Reply

Answer 12

??? go for trigo
SLloney

Answer 13

Lol, I can do this problem orally , I know how to solve these problems

Answer 14

then write

Answer 15

U have A =22.5
So u can calculate 3A ,5A , 7A ?

Answer 16

every one a small kid of class 5 know
think How will u crack IIT
I need answer not ideas of nursery

Answer 17

Okay so if you are allowed to use a calculator
It equals,

(1+cos22.5)(1+cos67.5)(1+cos112.5)(1+cos157.5)

Answer comes to be 0.125

Answer 18

(1+cos22.5)(1+cos67.5)(1+cos112.5)(1+cos157.5)
value? without using calculator its class 11 Q

Answer 19

challange for u
like IIT

Answer 20

cos(45)= 1/√2
cos(θ/2) = +/-sqrt [(1+cos(θ))/2]
cos(22.5) = +/- sqrt {1+cos(45)) /2]
= +/- sqrt [ (1+1/√2) /2]
= +/- sqrt [ (√2+1) / 2√2)]


Like that you can use the half-angle identity in trigonometry


Or i can give you another method

(1+cos22.5) (1+cos67.5)(1+cos 112.5)(1+cos 157.5)?
=(1+cos22.5) {1+cos(90−22.5)}{1+cos(90+22.5)} {1+cos(180−22.5)}
=(1+cos22.5) {1+sin22.5)}{1−sin22.5}{1−cos22.5}
=(1+cos22.5){1−cos22.5} {1+sin22.5}{1−sin22.5}
={1−cos²22.5} {1−sin²22.5}
={sin²22.5 cos²22.5}
={sin22.5 cos22.5}²
={(sin45)/2}² ={(1/√2)/2}²=1/8

Answer 21

best answer

Answer 22

Thank you! you are welcome

Answer 23

I thought you have to do with calculator , which is very dumb
that's why i was trolling nvm

Answer 24

Which class are you in

Answer 25

You have blocked me

Answer 26

:(

Answer 27

Its time for u to prepare only for IIT not for chatting thats why I block you
bye over

Answer 28

LOL, okay
Which class are you in

Answer 29

Bye its close
all the best but behind me
look on 2016 result my name in the TOPPER
& YOU ARE FOLLWER
sorry &bye

Answer 30

What ?????