Question

If, m+n=5 and mn=6 then, = ?
${m}^{2} + {n}^{2} \times {m}^{3} + {n}^{3}$
​

Answer 1

Answer:

Squaring on both the sides !!!

(m + n)^2 = 25

25= m^2 + 2mn + n^2

25 = m^2 + n^2 + 2(6)

m^2 + n^2 = 25 - 12

m^2 + n^2 = 13

now

m^3 + n^3 = (m+n)(m^2 - mn + n^2)

m^3 + n^3 = 5 ( 13 - 6 )

= 5 × 7

=35

therefore;

({m}^{2} + {n}^{2} )({m}^{3} + {n}^{3} )(m

2

+n

2

)(m

3

+n

3

)

13×35 = 455