Question

teta = 2 sec^-1 3/sqrt5 . find the values of sin teta / 2

Answer 1

\[\theta= 2 \sec ^{-1} \frac{ 3 }{ \sqrt{5} }\] find the values of \[\sin \frac{ \theta }{ 2 }\]

Answer 2

Tips: use \( instead of \[ to make equations in line :)

Answer 3

okay

Answer 4

@hartnn

Answer 5

\[\theta=2\sec^{-1}\frac3{\sqrt5}\]\[\frac\theta2=sec^{-1}\frac3{\sqrt5}\]\[\sec\frac\theta2=\frac3{\sqrt5}\]\[\cos\frac\theta2=\frac{\sqrt5}3\]

Answer 6

yes, just find sin from that triangle!

Answer 7

just like the calculation above ?

Answer 8

because you question was basically
sin (sec inv 3/sqrt 5)

Answer 9

ermm

Answer 10

What is \(\sin\dfrac\theta2\) from this triangle? :)

Answer 11

\[\frac{ 2 }{ \sqrt{5}}\]

Answer 12

is it ?

Answer 13

sine is opposite / hypotenuse

Answer 14

ops , confused with tan

Answer 15

2/3

Answer 16

yessss

Answer 17

bingo :D

Answer 18

i see , okay , that's my last question . thank you guys , good night ! :)

Answer 19

wait if sin teta , is the answer still te same ?

Answer 20

\(\sin\theta=\sin\left(2\cdot\dfrac\theta2\right)=2\sin\dfrac\theta2\cos\dfrac\theta2\)

Answer 21

why do we need to times 2 ?

Answer 22

^
and you can find both sin theta/2 and cos theta/2 using the triangle

Answer 23

because its the standard formula
\(\huge \sin 2A = 2 \sin A \cos A\)

Answer 24

oh , that formula

Answer 25

so the answer is \[\frac{ 4.\sqrt{5} }{ 3 }\] ?

Answer 26

no....
what did u use for cos theta/2 ?

Answer 27

by the way that little dot is produced by \cdot :)

Answer 28

\[\frac{ \sqrt{5} }{ 3 }\]

Answer 29

thats correct
so shouldn't u get
4 sqrt 5/ 9?

Answer 30

i forgot to times the denomenator

Answer 31

yup i got 4sqrt5/9

Answer 32

then correct.

Answer 33

good job :)

Answer 34

again thank you , awesome supermaths tutor

Answer 35

:D lets sleep

Answer 36

no problem :)

Answer 37

where you from? :)