document.write( "Question 119631This question is from textbook Trigonometry
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\n" ); document.write( "\n" ); document.write( "x^6-64 = 0
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Algebra.Com's Answer #87728 by jim_thompson5910(35256)\"\" \"About 
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\"x%5E6-64=0\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2-4%29%28x%5E4%2B4x%5E2%2B16%29=0\" Factor the left side by using the difference of cubes formula\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B2%29%28x-2%29%28x%5E4%2B4x%5E2%2B16%29=0\" Factor \"x%5E2-4\" to get \"%28x%2B2%29%28x-2%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now set each factor equal to zero:\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B2=0\", \"x-2=0\" or \"x%5E4%2B4x%5E2%2B16=0\"\r
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\n" ); document.write( "\n" ); document.write( "Now solve for x for the first two factors:\r
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\n" ); document.write( "\n" ); document.write( "\"x=-2\", \"x=2\" or \"x%5E4%2B4x%5E2%2B16=0\"\r
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\n" ); document.write( "\n" ); document.write( "So the first two roots are \"x=-2\" or \"x=2\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's solve \"x%5E4%2B4x%5E2%2B16=0\"\r
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\n" ); document.write( "\n" ); document.write( "Let \"w=x%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"w%5E2%2B4w%2B16=0\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for w:\r
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\n" ); document.write( "\n" ); document.write( "Starting with the general quadratic\r
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\n" ); document.write( "\n" ); document.write( "\"aw%5E2%2Bbw%2Bc=0\"\r
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\n" ); document.write( "\n" ); document.write( "the general solution using the quadratic equation is:\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"\r
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\n" ); document.write( "\n" ); document.write( "So lets solve \"w%5E2%2B4%2Aw%2B16=0\" ( notice \"a=1\", \"b=4\", and \"c=16\")\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+sqrt%28+%284%29%5E2-4%2A1%2A16+%29%29%2F%282%2A1%29\" Plug in a=1, b=4, and c=16\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+sqrt%28+16-4%2A1%2A16+%29%29%2F%282%2A1%29\" Square 4 to get 16 \r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+sqrt%28+16%2B-64+%29%29%2F%282%2A1%29\" Multiply \"-4%2A16%2A1\" to get \"-64\"\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+sqrt%28+-48+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+4%2Ai%2Asqrt%283%29%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"w+=+%28-4+%2B-+4%2Ai%2Asqrt%283%29%29%2F%282%29\" Multiply 2 and 1 to get 2\r
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\n" ); document.write( "\n" ); document.write( "After simplifying, the quadratic has roots of\r
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\n" ); document.write( "\n" ); document.write( "\"w=-2+%2B+2%2Asqrt%283%29i\" or \"w=-2+-+2%2Asqrt%283%29i\"\r
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\n" ); document.write( "\n" ); document.write( "Remember, \"w=x%5E2\". So \"x%5E2=-2+%2B+2%2Asqrt%283%29i\" or \"x%5E2=-2+-+2%2Asqrt%283%29i\"\r
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\n" ); document.write( "\n" ); document.write( "Now take the square root of both sides for each case\r
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\n" ); document.write( "\n" ); document.write( "\"x=0%2B-sqrt%28-2+%2B+2%2Asqrt%283%29i%29\" or \"x=0%2B-sqrt%28-2+-+2%2Asqrt%283%29i%29\"\r
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\n" ); document.write( "\n" ); document.write( "Now break up the plus/minus\r
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\n" ); document.write( "\n" ); document.write( "\"x=sqrt%28-2+%2B+2%2Asqrt%283%29i%29\", \"x=-sqrt%28-2+%2B+2%2Asqrt%283%29i%29\", \"x=sqrt%28-2+-+2%2Asqrt%283%29i%29\", or \"x=-sqrt%28-2+-+2%2Asqrt%283%29i%29\"\r
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\n" ); document.write( "\n" ); document.write( "So the roots of \"x%5E6-64=0\" are \r
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\n" ); document.write( "\n" ); document.write( "\"x=-2\", \"x=2\", \"x=sqrt%28-2+%2B+2%2Asqrt%283%29i%29\", \"x=-sqrt%28-2+%2B+2%2Asqrt%283%29i%29\" or \"x=sqrt%28-2+-+2%2Asqrt%283%29i%29\", or \"x=-sqrt%28-2+-+2%2Asqrt%283%29i%29\"
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