For the question:
sin b =3/7 . what is cos b equal too considering it is an obtuse angle
i did c=sqrt(a^2+b^2)
sin = opposite/hypotenuse
so the adjacent length is 2*sqrt(10)
cos=adjacent/hypotenuse
so, cos b = 2*sqrt(10)/7
the angle is obtuse so,
pi-(2*sqrt(10)/7)= cos b (as an integer, 154 degrees)
is this definitely the right answer?
also i did all that but i put:
pi+(2*sqrt(10)/7)
Do you think ill only lose one mark?
Also on question 9, it said: 'List the values of y which allow the sequence to have a sum to infinity'
(or words to that affect)
i put 0<y<1 because a log cannot be a negative value
Anyone got an unofficial mark scheme by any chance?