Question

x+y=5 and xy=4 find the value of x^3+y^3

Answer 1

Solution:

X + Y = 5

⇒Y = 5 - X

also, XY = 4

X(5 - X) = 4

5X - X² = 4

X² - 5X + 4 = 0

solving it

we get X₁ = 4 and X₂ = 1

also Y₁ = 1 and Y₂ =4

X₁³ + Y₁³ =  4³ + 1³ =65

also X₂³ + Y₂³ = 1³ + 4³ = 65

therefore,

X³ + Y³ = 65

Hope that helped you

Please mark my answer as Brainliest!