+28 which solutions have the equation sin x=cos(pi/4) in the range 0 < x < 2pi ?
A) Only x=pi/6
B) x= pi/4 and x=5pi/4
C) x= pi/4 and x=3pi/4
D) Only x=pi/4
E) none of the options is correct
How many soutions have the equaton sin x= sin(pi/7) in the ange 0 < x < pi
A) none of the options is correct
B) No solutions
C) exactly one solutions
D) exactly two solutuons
E) exactly three solutions
+36916 The first one is 'C' where sinx = + sqrt2/2 is in 1 st and 2 nd quadrants pi/4 and 3pi/4
The second one is 'D' at pi/7 and 6pi/ 7 sin has the same positive value.
(Sin is negative from pi to 2pi....thought the question only asked about 0-->pi )
