since cos^2 = 1-sin^2,
1-sin^2A - sin^2A - sinA = 0
2sin^2A + sinA - 1 = 0
(2sinA-1)(sinA+1) = 0
sinA = 1/2 or -1
A = 30,150,270
Solve the equation cos^2A = sin^2A + sinA when 0¨¬¡A¡360¨¬. Select all the solutions from the list below.
A. 330 degrees
B. 270 degrees
C. 150 degrees
D. 30 degrees
1 answer
2 answers