Question

hellpppp

Answer 1

isn't that 1?

Answer 2

f'(x) = 2Cosx - 2Sin2x = 0

Answer 3

solve for x:
2Cosx - 2Sin(2x) = 0

Answer 4

x = (1/2) pi (4*n-1), where n is an integer

Answer 5

the only solution in the given interval is:
x = 3pi/2

Answer 6

So plug each endpoint and the solution into the equation:
x=0
y= 2Sin0 + Cos(2*0) = 0 + 1 = 1

Answer 7

x = 3pi/2
y = 2Sin(3pi/2) + Cos(3pi) = -3

Answer 8

And finally, 2pi:
x = 2pi
y = 2Sin(2pi) + Cos(4pi) = 1

Answer 9

Thus the maximum of y is equal to 1, which is none of the above, which is option 1.

Answer 10

thank you so much! what would be the absolute minimun?

Answer 11

absolute minimum is y=-3, which occurs at x = 3pi/2 (assuming the interval's the same)

Answer 12

oh ok and to find all the solutions for sec4x=2 , i solved it and i got pi/12 but i dont know how to find the other solutions