use an identity to solve the equation on the interval 0,2π).\n\\( \\sin ^ { 2 } x - 5 \\cos x + 5 = 0…

use an identity to solve the equation on the interval 0,2π).\n\\( \\sin ^ { 2 } x - 5 \\cos x + 5 = 0 \\)\nwhat is the solution in the interval 0,2π)?\nselect the correct choice below and, if necessary, fill in the answer box to complete your choice.\na. \\( x = \\) (type your answer in radians. use integers or fractions for any numbers in the expression. type an exact answer\nb. there is no solution.
Answer
Explanation:
Step1: Use the Pythagorean identity
We know that (\sin^{2}x = 1-\cos^{2}x). Substitute this into the given equation (\sin^{2}x-5\cos x + 5=0). We get (1-\cos^{2}x-5\cos x + 5=0).
Step2: Simplify the equation
Rearrange the terms: (-\cos^{2}x-5\cos x+6 = 0). Multiply through by (- 1) to get (\cos^{2}x + 5\cos x-6=0). Let (t=\cos x), then the equation becomes (t^{2}+5t - 6=0).
Step3: Solve the quadratic equation
Factor the quadratic equation (t^{2}+5t - 6=(t + 6)(t - 1)=0). Set each factor equal to zero: (t+6 = 0) gives (t=-6), and (t - 1=0) gives (t = 1).
Step4: Substitute back (t=\cos x)
Since (-1\leqslant\cos x\leqslant1), (\cos x=-6) is rejected. For (\cos x=1), and (x\in[0,2\pi)), we know that (x = 0).
Answer:
A. (x = 0)