That means you first calculate divide and multiply and at the and plus and minus.
So
12 / 2 + 4 - 2 x 3 =
6 + 4 - 6 = 4
(7, 3) is the answer I believe

by using the integration formula
we get,

now put the value of t=\sin\theta in the above equation
we get,

hence proved
13=1+4s
So you find S
So you take out 1, and subtract 1 from thirteen
12=4s so then you divide it by 4
12÷4=3
s=3