ax2+bx+c=0a,b,c∈{1,2,3,4,5,6,7,8} Repeated roots D=0⇒b2−4ac=0⇒b2=4ac Prob =8×8×88=641⇒(a,b,c)(1,2,1);(2,4,2);(1,4,4);(4,4,1);(3,6,3);(2,8,8);(8,8,2);(4,8,4)8 case
The coefficients a,b,c in the quadratic equation ax2+bx+c=0 are chosen from the set {1,2,3,4,5,6,7,8}. The probability of this equation having repeated roots is :
Held on 5 Apr 2024 · Verified 6 Jul 2026.
1281
641
2563
1283
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