cosine rule

[slender kindle]

for this question how did they know to use cosine rule because i just used pythagoras

[digital minnow]

because you will be able to know the angle at 8 o'clock

[slender kindle]

why do u need to know the angle for the distance?

probably sound dumb but just for my own understanding

[digital minnow]

to use cosine rule

for pythagoras you need 90 angle

[slender kindle]

ohhh i see

[digital minnow]

which prob gonna take longer to work out

[slender kindle]

so i cant just assume its pythagoras got it

[digital minnow]

but with cos rule you just beed to know 2 length and the angle opposite of the unknown length

[slender kindle]

yh

ah okay thanks

[pulsar dirge]

is it smth like this?

[slender kindle]

yh

i didnt realise the angle tho

[pulsar dirge]

i had some weird method to work out the angle

💀

[slender kindle]

u are right tho

then u use cosine to find that length

[pulsar dirge]

yee

[slender kindle]

like if it came up in an exam i would never get that

thats the problem

[pulsar dirge]

but now u can

[slender kindle]

how did u know it was 120

[pulsar dirge]

basically

i knew these were 90 degrees

and i did 360/12 to get 30

so the angle made with each hour is 30 if that makes sense

some goofy way xd

[slender kindle]

ohhhh thats acc smart

[pulsar dirge]

nah 😂

theres prolly an easier way

just cant think of it

[slender kindle]

nah i think it works

corbett maths doesnt acc explain it properly

like the answer

but this acc helped

so thanks

[pulsar dirge]

i think it works like this

each time going up in 30 degrees

doesnt make sense tho ik cuz circle is 360 degrees but yeah whatever