Question

determine whether the given quadratic equation has root. if so find the root. -2y2+y+1=0

Answer 1

$-2 {y}^{2} + y + 1 = 0 \\ 2 {y}^{2} - y - 1 = 0 \\ 2 {y}^{2} - 2y + y - 1 \\ 2y(y - 1) + 1(y - 1) \\( 2y + 1)(y - 1) = 0 \\ \\ \\ y = 1 \\ \\ y = - 1/2$

Answer 2

Answer:

Sum of n terms in AP is

S = n/2[ a+ l]

Where,

n is the number of terms

a is the first term

l is the last term

So the sum of the given series (S)=

S = 7×[1 +13]/2

S = 7×14/2

S = 7×7 = 49