Question

Please Solve the equaction (7a2+8b2-5v2)

Answer 1

7a^2+8b^2-5v^2
(7a+8b-5v)^2
7a^2+8b^2+(-5v)^2+2×7a×8b+2×8b×(-5v)+2×(-5v)×(7a)
49a^2+64b^2+25v^2+112ab-80bv-70av(Answer)(∩︵∩)(∩︵∩)(∩︵∩)

Answer 2

$= 7 {a}^{2} + 8 {b}^{2} - 5 {v}^{2}$

$= {(7a + 8b - 5v)}^{2}$

$using \: the \: identity (x + y + z)^{2} = {x}^{2} + {y}^{2} + {z}^{2} + 2xy + 2yz + 2zx$

$= {(7a)}^{2} + {(8b)}^{2} + ( - 5v) ^{2} + (2 \times 7a \times 8b) + (2 \times 8b \times - 5v) + (2 \times - 5v \times 7a)$

$= 49 {a}^{2} + 64{b}^{2} - 25 {v}^{2} + 96ab - 80bv - 70ab$

$......hope \: you \: got \: it.$