# trigonometric identities a level maths question

im tryna make the first line equal 3 root 3 but I got 2 root 3
Original post by esha06
im tryna make the first line equal 3 root 3 but I got 2 root 3

Line 3 is ok, but then theres errors in both the sin and cos coeffs. Wont mention about the 6 near the end or what happens to the sin. Just work it through using the usual algebra.
(edited 6 months ago)
Original post by mqb2766
Line 3 is ok, but then theres errors in both the sin and cos coeffs. Wont mention about the 6 near the end or what happens to the sin. Just work it through using the usual algebra.

did it 😭😭😭
Original post by esha06
did it 😭😭😭

Looks good. Small tip would be to try and make coeffs positive so if you have 1 sin on one side of the equation and 1/2 sin the other, the obv thing to do is to rearrange to get 1/2 sin rather than -1/2 sin.
Original post by mqb2766
Looks good. Small tip would be to try and make coeffs positive so if you have 1 sin on one side of the equation and 1/2 sin the other, the obv thing to do is to rearrange to get 1/2 sin rather than -1/2 sin.

i kept the sin and cos and different sides because i thought im gonna divide them later so it would be easier maybe?
Original post by esha06
i kept the sin and cos and different sides because i thought im gonna divide them later so it would be easier maybe?

Sure but if youd swapped sides on line 4, both coeffs would be positive and theres less to do/fewer potential errors.
Original post by mqb2766
Sure but if youd swapped sides on line 4, both coeffs would be positive and theres less to do/fewer potential errors.

trueeee i like to make stupid mistakes as well 😭