Question

what is the formula of a2-b2-ç2​

Answer 1

Answer:

$a^2 -b^2 - c^2 = (a - b - c)(a+b+c) + 2bc$

Step-by-step explanation:

$a^2 - b^2 - c^2 = a^2 - (b^2+c^2)$

$=a^2 - [(b+c)^2 -2bc]$

$=a^2 -(b+c)^2 + 2bc$

$=\left[a^2 - (b+c)^2\right] + 2bc$

$=\left[ \left[ a - (b + c)\right] [a+(b+c)\right] + 2bc$

$=(a-b-c)(a+b+c) + 2bc$