Question

P2+q2=5 and pq=2 then find the value of p3-q3

Answer 1

Answer:

±7

Step-by-step explanation:

Given: p^2+q^2=5 & pq=2

Need to find: value of p^3-q^3

Lets rewrite p^3-q^3 as

p^3-q^3=(p-q)(p^2+pq+q^2)

We need to find value of p-q using given data:

(p-q)^2=p^2+q^2-2pq=5-4=1 => (p-q)^2=1 => p-q=±1

Now, lets find it:

p^3-q^3=(p-q)(p^2+pq+q^2)=±1*(5+2)=±7

Answer 2

Step-by-step explanation:

Answer:

±7

Step-by-step explanation:

Given: p^2+q^2=5 & pq=2

Need to find: value of p^3-q^3

Lets rewrite p^3-q^3 as

p^3-q^3=(p-q)(p^2+pq+q^2)

We need to find value of p-q using given data:

(p-q)^2=p^2+q^2-2pq=5-4=1 => (p-q)^2=1 => p-q=±1

Now, lets find it:

p^3-q^3=(p-q)(p^2+pq+q^2)=±1*(5+2)=±7