If sinθ and cos θ are the roots of ax^2+bx+c then what is the relation between a, b and c?

Answer 1

(x-sinA)(x-cosA)

= x^2 -(sinA+cosA)x +sinAcosA

= ax^2 +bx + c

a=1, b = -sinA-cosA, c = sinAcosA

just set the coefficients of the x^2 term equal.

a=1

Same with the coefficients of the x term

b =-sinA-cosA

and set the constant terms equal.

c= sinAcosA

if SinA and CosA are roots, then the factors are x-SinA and x-CosA. Multiply the factors together