if (x^2+x+1) is written in the form (x+1/2)^2+q^2 find the possible value of q
pls guys help to do this sum
Answers
Answer:
Step-by-step explanation:
± √3/2 or ± √(3/4)
Step-by-step explanation:
Since both are same, just written in other forms, we can say
⇒ x² + x + 1 = (x + 1/2)² + q²
⇒ x² + x + 1 = x² + (1/2)² + 2(x)(1/2) + q²
⇒ x² + x + 1 = x² + 1/4 + x + q²
⇒ 1 = 1/4 + q²
⇒ 1 - 1/4 = q²
⇒ 3/4 = q²
⇒ ± √(3/4) = q or ± √3/2 = q
Answer:
Solution :-
Given, p and q be the roots of the equation
x
2
−2x+A=0. So,
p+q=22.....(1)
pq=A...(2)
And, r and s be the roots of the equation
x
2
−18+B=0. So,
r+s=18...(3)
rs=B...(4)
Now, p,q,r and s are in A.P
so let, p=a,q=a+d,r=a+2d,s=a+3d
Now, put these values in equation (1) and (3), we have
a+a+d=2⇒2a+d=2...(5)
And,
a+2a+a+3d=18⇒2a+5d=18...(6)
solving equation (5) and (6),
a=−1, d=4
so p=−1,q=−1+4=3,r=−1+8,s=−1+12=11
Thus,
A=pq=−1×3=−3
B=rs=7×11=77
Then A+B=−3+77=74