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# trig mk9 watch

tanx=cosx

sinx=cos²x

sinx=1-sin²x

sin²x+sinx-1=0

let sinx=y

y²+y-1=0

quaratic equation gives me (-1±root 2)/2

then i got a wrong answer >.>
help, where have i made a stupid mistake this time

TeeEm Zacken
2. (Original post by thefatone)

tanx=cosx

sinx=cos²x

sinx=1-sin²x

sin²x+sinx-1=0

let sinx=y

y²+y-1=0

quaratic equation gives me (-1±root 2)/2

then i got a wrong answer >.>
help, where have i made a stupid mistake this time

TeeEm Zacken
sorry I am teaching
3. (Original post by TeeEm)
sorry I am teaching
oh.. ok
4. (Original post by thefatone)

tanx=cosx

sinx=cos²x

sinx=1-sin²x

sin²x+sinx-1=0

let sinx=y

y²+y-1=0

quaratic equation gives me (-1±root 2)/2

then i got a wrong answer >.>
help, where have i made a stupid mistake this time

TeeEm Zacken
There's where.
5. (Original post by thefatone)

tanx=cosx

sinx=cos²x

sinx=1-sin²x

sin²x+sinx-1=0

let sinx=y

y²+y-1=0

quaratic equation gives me (-1±root 2)/2

then i got a wrong answer >.>
help, where have i made a stupid mistake this time

TeeEm Zacken
As above, solving the quadratic equation gives:

6. 1 + 4 = 5 not 2
7. (Original post by Zacken)
As above, solving the quadratic equation gives:

(Original post by the bear)
1 + 4 = 5 not 2
thanks guys so much, i was being stupid again >.>
8. (Original post by the bear)
1 + 4 = 5 not 2
9. (Original post by Zacken)
claiming this gif for future use
10. (Original post by Zacken)

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