Answer:
A and C
Step-by-step explanation:
Given
2cos²x - 2 = 0 ( add 2 to both sides )
2cos²x = 2 ( divide both sides by 2 )
cos²x = 1 ( take the square root of both sides )
cos x = ± [tex]\sqrt{1}[/tex] = ± 1
cos x = 1 ⇒ x = [tex]cos^{-1}[/tex](1) = 0°
cos x = - 1 ⇒ x = [tex]cos^{-1}[/tex](- 1) = 180°
Answer:
2 possible results
0° and 180°
Step-by-step explanation:
2cos² x– 2 = 0 (add 2 to both sides)
2cos² x = 2 (divide both sides by 2)
cos² x = 2/2
cos² x = 1
cos x = ±√1
cos x = ±1
because the range of x is not stated, there are 2 possible results for x that will cause cos x to be either 1 or -1
0° and 180°
