document.write( "Question 11060: say you have the equation y = x^3 - 3. How would you solve the y-intercept, the x-intercept and the vertex to this equation? \n" ); document.write( "
Algebra.Com's Answer #5796 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
The y-intercept for \"y+=+x%5E3+-+3\" is found by setting x = 0.\r
\n" ); document.write( "\n" ); document.write( "\"y+=+%280%29%5E3+-+3\"
\n" ); document.write( "\"y+=+-3\" The y-intercept is at (0, -3)\r
\n" ); document.write( "\n" ); document.write( "The vertex? This question would make sense for a quadratic equation, but you have a cubic (third degree) equation and these have no vertex (maximum or minimum). The best you can do for a cubic function is to find the relative maximum or relative minimum, if there is one.
\n" ); document.write( "Take a look at the grah of this function and you'll see what I mean.\r
\n" ); document.write( "\n" ); document.write( "\"graph%28300%2C200%2C-5%2C5%2C-5%2C5%2Cx%5E3-3%29\"\r
\n" ); document.write( "\n" ); document.write( "You can see that the y-intercept is (o, -3) but the vertex?\r
\n" ); document.write( "\n" ); document.write( "Perhaps you meant to type: \"y+=+x%5E2+-+3\" ??\r
\n" ); document.write( "\n" ); document.write( "Let's see what that looks like.\r
\n" ); document.write( "\n" ); document.write( "\"graph%28300%2C200%2C-5%2C5%2C-5%2C5%2Cx%5E2-3%29\"\r
\n" ); document.write( "\n" ); document.write( "The y-intercept is found, as before, by setting x = 0.\r
\n" ); document.write( "\n" ); document.write( "\"y+=+%280%29%5E2+-+3\"\r
\n" ); document.write( "\n" ); document.write( "The y-intercept is at (0, -3) as you can see on the graph.\r
\n" ); document.write( "\n" ); document.write( "The x-coordinte of the vertex is found by:
\n" ); document.write( " \"x+=+-b%2F2a\"
\n" ); document.write( "\"x+=+-%280%29%2F2\"
\n" ); document.write( "\"x+=+0\" and the y-coordinate of the vertex is found by substituting this value of x into the original equation and solving for y.\r
\n" ); document.write( "\n" ); document.write( "\"y+=+%280%29%5E2+-+3\"
\n" ); document.write( "\"y+=+-3\"\r
\n" ); document.write( "\n" ); document.write( "The y-coordinate is y = -3.\r
\n" ); document.write( "\n" ); document.write( "So the vertex is at (0, -3)
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