Sagot :
For sin : First and second are positive Third and Fouth are negative
For cos : first and Fourth are positive, 270°-360°
For cos : first and Fourth are positive, 270°-360°
Answer:
When Ф lies in quadrant IV the value of cos Ф lies in [0, 1].
Step-by-step explanation:
Given the angle Ф lies in quadrant IV. we have to find the value of cos Ф
As we know, cos Ф is positive only in first and fourth quadrant i.e when Ф lies in 0<Ф<90 and 270<Ф<360.
Hence, cos Ф is positive when Ф lies in 1st and 4th quadrant.
& cos Ф is negative when Ф lies in 2nd and 3rd quadrant.
As, cosФ range from [-1,1]
but in 4th quadrant [0,1]
Hence, when Ф lies in quadrant IV the value of cos Ф lies in [0, 1].