Q. The given equation aimesx2+98x+c has at least 1 real root and a factor of kx+j. What is the greatest possible value of ac?
Discriminant Calculation: Since the equation has at least one real root, the discriminant must be non-negative.Discriminant: b2−4ac≥0Here, b=98, so:982−4ac≥0
Solve for ac: Rearrange to solve for ac:9604≥4acDivide both sides by 4:2401≥ac
Factorize Polynomial: Since kx+j is a factor, the polynomial can be written as:a(x−r)(x−s)Expanding:a(x2−(r+s)x+rs)Comparing with a⋅x2+98x+c:−a(r+s)=98 and ars=c
Maximize ac: To maximize ac, we need to maximize rs while keeping −a(r+s)=98.Let r=s for simplicity:−2ar=98So:ar=−49
Substitute ar: Substitute ar=−49 into ars=c:a(−49)r=cSo:c=−49r
Final Calculation: Now, ac=a⋅(−49r):ac=−49arSince ar=−49:ac=−49(−49)ac=2401
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