Question

if p and q are roots of p(x)=ax²+bx+c,where a not equal to zero then write the value of p+q

Answer 1

!! Hey Mate !!

Your answer is --

Given, p and q are the zeroes of given polynomial p(x)= ax^2+bx+c.

So, (x-p) & (x-q) are the factor of p(x)

therefore,

ax^2+bx+ c = k (x-p)(x-q) for some constant k

=> ax^2+bx+c = k(x^2-qx-px+pq)

=> ax^2 + bx + c = kx^2 -x(p+q)k + pqk

Now, comparing both side , we get

k = a , b = -(p+q)k & c = pqk

Now, take b = -(p+q)k


=> -(p+q) = b/k

=> -(p+q) = b/a { since , k = a }

=>[ p+q = - b/a ]



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【 Hope it helps you 】
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