Question

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

Answer 1

2p² − q² + 3r²

Substituting p = -2, q = -1 and r = 3 in the given expression:

\[2 \times ( - 2 )^2 - ( - 1 )^2 + 3 \times (3 )^2 = 2 \times ( - 2 \times - 2) - ( - 1 \times - 1) + 3 \times (3 \times 3)\] 

\[ \Rightarrow 8 - 1 + 27 = 34\]