document.write( "Question 539229: Find the magnitude and direction (in degrees) of the vector.
\n" ); document.write( "v = 3i +√7j
\n" ); document.write( "

Algebra.Com's Answer #353359 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
If v = ai+bj, then ||v|| = sqrt(a^2+b^2)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "In this case, a = 3 and b = sqrt(7)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "||v|| = sqrt(a^2+b^2)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "||v|| = sqrt(3^2+(sqrt(7))^2)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "||v|| = sqrt(9+7)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "||v|| = sqrt(16)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "||v|| = 4\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So the magnitude of v is 4\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "To find the direction or angle, we use the idea that theta = arctan(b/a)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "theta = arctan(b/a)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "theta = arctan(sqrt(7)/3)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "theta = 41.409622 (note: this is approximate)\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So the direction is roughly 41.409622 degrees.
\n" ); document.write( "
\n" ); document.write( "
\n" );