maths
posted by sarah .
Choose three options which are true:
a) an angle of 150 degrees is equivalent to 2pie/3 radians.
b) Cos 0 = cos (0 – pie/2) for al values of 0.
c) Sin 0 = cos (0 – pie/2) for all values of 0.
d) If triangle ABC has a right angle at B, then sin A = cos C
e) In any triangle ABC, if the lengths of just two sides of the triangle are known, then you always calculate the third.
f) In any triangle ABC,AB sin C = AC sin B
g) If triangles PQR and XYZ are similar, with P = X, Q = Y, R = Z, then XY/PQ = XZ/PR
h) In any triangle PQR, cos R = PR^2 + PQ^2 – QR^2/ 2 x PR x PQ.
CAN ANY 1 HELP ME ON WHICH 3 OPTIONS ARE RIGHT??
Which have you eliminated? I takes just a min to go through each ansewer.
i think its d and e and i don't knw wat cod be the third option, is this ryt?
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