We need to find the values of x that satisfy the equation 2sin2(x)−2cos(x)=0. We can use the trigonometric identity sin2(x)+cos2(x)=1 to express sin2(x) in terms of cos2(x). sin2(x)=1−cos2(x) Substituting this into the equation, we get:
2(1−cos2(x))−2cos(x)=0 2−2cos2(x)−2cos(x)=0 Rearranging the terms, we get a quadratic equation in terms of cos(x): 2cos2(x)+2cos(x)−2=0 Let y=cos(x). Then the equation becomes: 2y2+2y−2=0 We can solve for y using the quadratic formula: y=2a−b±b2−4ac where a=2, b=2, and c=−2. y=2(2)−2±(2)2−4(2)(−2) y=4−2±2+16 y=4−2±18 y=4−2±32 So we have two possible values for y: y1=4−2+32=422=22 y2=4−2−32=4−42=−2 Since y=cos(x), we have cos(x)=22 or cos(x)=−2. Since −1≤cos(x)≤1, the second solution cos(x)=−2 is not possible as −2≈−1.414. Therefore, cos(x)=22. The values of x for which cos(x)=22 are x=4π+2nπ and x=−4π+2nπ, where n is an integer. We can also write x=47π+2nπ. Combining the two solutions gives x=±4π+2nπ, where n is an integer.