 Home
 Discuss
 Home Work Help
 solve the following quadratic equation:
 Entrance Exam
 Home Work Help

0
questions
0
answers
Question
solve the following quadratic equation:
Expert Reply
Answer : Given : x^{2}(5i)x+(18+i)=0
now , we know here a= 1 , b = i  5 , c = 18
D = b^{2}  4 ac
= ( i5 )^{2}  4 (18+ i)
= i^{2} + 5^{2}  2 ( i ) (5 ) 72 4i { using ( ab)^{2} = a ^{2} + b^{2}  2ac }
=>D = 48 14 i = 2i ( 24 + 7i )
squareroot (D) = i *square root (2) * ( square root (24 + 7i) )
{ applying sqaure root formula of a complex number}
squareroot (D) = i 2^{1/2 }( 1/2^{1/2})( 7 + i)
= 7i 1 or 7i + 1
the two roots will be : (b + D^{1/2}) /2 and (b  D^{1/2}) /2
((5i) + ( 7i 1) ) /2 and ((5i)  ( 7i 1) ) /2
2+ 3i and 34i are the required two roots Answers
Home Work Help