document.write( "Question 1210538: Find the values of x in the range 0°≤x≤360°, which satisfy the equation below\r
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document.write( "i) sin3xsinx = 2cos2x + 1\r
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document.write( "ii) 3cotx + tanx - 4 = 0
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Algebra.Com's Answer #853497 by CPhill(2189) You can put this solution on YOUR website! To solve these trigonometric equations, we will use fundamental identities to simplify them into a solvable form.\r \n" ); document.write( "\n" ); document.write( "---\r \n" ); document.write( "\n" ); document.write( "## i) \r \n" ); document.write( "\n" ); document.write( "To solve this, we can use the **Product-to-Sum formula**:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "**Step 1: Apply the formula to the left side.** \n" ); document.write( "Let and :\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "**Step 2: Simplify and rearrange.** \n" ); document.write( "Multiply the entire equation by :\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "**Step 3: Use the Double Angle formula for .** \n" ); document.write( "Recall that . Here, let :\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "**Step 4: Factor the quadratic.** \n" ); document.write( "Let :\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So, or .\r \n" ); document.write( "\n" ); document.write( "**Step 5: Solve for in the range .** \n" ); document.write( "Since , then .\r \n" ); document.write( "\n" ); document.write( "* **Case 1: **\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "* **Case 2: **\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "**Solution (i):** \r \n" ); document.write( "\n" ); document.write( "---\r \n" ); document.write( "\n" ); document.write( "## ii) \r \n" ); document.write( "\n" ); document.write( "**Step 1: Rewrite in terms of .** \n" ); document.write( "Since , the equation becomes:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "**Step 2: Form a quadratic equation.** \n" ); document.write( "Multiply through by (noting that ):\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "**Step 3: Factor the quadratic.**\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So, or .\r \n" ); document.write( "\n" ); document.write( "**Step 4: Solve for in the range .**\r \n" ); document.write( "\n" ); document.write( "* **Case 1: **\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "* **Case 2: **\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "**Solution (ii):** \r \n" ); document.write( "\n" ); document.write( "---\r \n" ); document.write( "\n" ); document.write( "Would you like me to show you how to verify these solutions using their respective graphs? \n" ); document.write( " |