document.write( "Question 1210538: Find the values of x in the range 0°≤x≤360°, which satisfy the equation below\r
\n" ); document.write( "\n" ); document.write( "i) sin3xsinx = 2cos2x + 1\r
\n" ); document.write( "\n" ); document.write( "ii) 3cotx + tanx - 4 = 0
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Algebra.Com's Answer #853497 by CPhill(2189)\"\" \"About 
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
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\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
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\n" ); document.write( "\n" ); document.write( "**Step 1: Apply the formula to the left side.**
\n" ); document.write( "Let and :\r
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\n" ); document.write( "\n" ); document.write( "**Step 2: Simplify and rearrange.**
\n" ); document.write( "Multiply the entire equation by :\r
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\n" ); document.write( "\n" ); document.write( "**Step 3: Use the Double Angle formula for .**
\n" ); document.write( "Recall that . Here, let :\r
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\n" ); document.write( "\n" ); document.write( "**Step 4: Factor the quadratic.**
\n" ); document.write( "Let :\r
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\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
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\n" ); document.write( "\n" ); document.write( "* **Case 2: **\r
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\n" ); document.write( "\n" ); document.write( "**Solution (i):** \r
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\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
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\n" ); document.write( "\n" ); document.write( "**Step 2: Form a quadratic equation.**
\n" ); document.write( "Multiply through by (noting that ):\r
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\n" ); document.write( "\n" ); document.write( "**Step 3: Factor the quadratic.**\r
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\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
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\n" ); document.write( "\n" ); document.write( "* **Case 2: **\r
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\n" ); document.write( "\n" ); document.write( "**Solution (ii):** \r
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\n" ); document.write( "\n" ); document.write( "Would you like me to show you how to verify these solutions using their respective graphs?
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