document.write( "Question 1005216: Find all solutions if 0° ≤ θ < 360°. Verify your answer graphically. (Enter your answers as a comma-separated list.)
\n" ); document.write( "cos 3θ = 1\r
\n" ); document.write( "\n" ); document.write( "3θ = 0°+360°k\r
\n" ); document.write( "\n" ); document.write( "(3θ)/3 = (0°+360°k)/3\r
\n" ); document.write( "\n" ); document.write( "θ = 0°+120°k\r
\n" ); document.write( "\n" ); document.write( "If k is 0 then θ = 0°
\n" ); document.write( "If k is 1 then θ = 120°
\n" ); document.write( "If k is 2 then θ = 240°
\n" ); document.write( "If k is 3 then θ = 360°\r
\n" ); document.write( "\n" ); document.write( "So shouldn't the answer be 0°, 120°, 240°, and 360°?\r
\n" ); document.write( "\n" ); document.write( "I thought I solved it correctly, but my answer keeps being flagged as incorrect. Any help would be greatly appreciated. Thank you \n" ); document.write( "

Algebra.Com's Answer #621548 by josgarithmetic(39617) $\"\"$ $\"About$

You can put this solution on YOUR website!
Your work looks good. The only trouble may be you did not pay strict attention to the inequality statement specified for the solution. $\"0%3C=theta%3C360\"$ means you must exclude 360 degrees. The angle can be 0, or 120, or 240 degrees. \n" ); document.write( "

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