Question

If p = −2, q = −1 and r = 3, find the value of p² + q² − r²

Answer 1

\[p^2 + q^2 - r^2\]

Substituting p = -2, q = -1 and r = 3 in the given expression:
\[( - 2 )^2 + ( - 1 )^2 - (3 )^2 = ( - 2 \times - 2) + ( - 1 \times - 1) - (3 \times 3)\]
\[ \Rightarrow 4 + 1 - 9 = - 4\]