document.write( "Question 137253: What is the solution to x^2-2x+5=0 when you use complex numbers. I always end up with 1-2i and 1+2i but when I put those into the equation to check it, it doesn't come out to be 0. Is that because it is a complex number and there truly is no solution? This question did not come from a textbook but from a worksheet from the tescher. The text we use is the Glencoe Algebra 2 text. It didn't help when I tried to follow the examples given. \n" ); document.write( "
Algebra.Com's Answer #100423 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! What is the solution to x^2-2x+5=0 when you use complex numbers. I always end up with 1-2i and 1+2i but when I put those into the equation to check it, it doesn't come out to be 0. \n" ); document.write( "---------------- \n" ); document.write( "x^2-2x+5 = 0 \n" ); document.write( "x = [2 +- sqrt(4-4*5)]/2 \n" ); document.write( "x = [2 +- sqrt(-16)]/2 \n" ); document.write( "x = [2 +- 4i]/2 \n" ); document.write( "x = [1 +-2i] \n" ); document.write( "------------------- \n" ); document.write( "Checking x = 1+2i \n" ); document.write( "(1+2i)^2 -2(1+2i) + 5 = 0 \n" ); document.write( "1-4+4i -2 -4i +5 = 0 \n" ); document.write( "(1-4-2+5)+(4i-4i) = 0 \n" ); document.write( "0 + 0i = 0 \n" ); document.write( "It checks \n" ); document.write( "============ \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " |