Question

Substrate 2a(a+b+c)-2b(a+b-c) from 2c(-a+b-c)​

Answer 1

Answer:

$a^{2} -b^{2} -c^{2}$

Step-by-step explanation:

2c(a+b-c)- [2a(a+b+c) - 2b(a+b-c)]

$2ca+2cb-2c^{2} - [2a^{2} +2ab+2ac- 2ba-2b^{2} +2bc]$

$2ca+2cb-2c^{2} -[2a^{2} +2ac-2b^{2} +2bc]$

$2ca+2cb-2c^{2} -2a^{2}-2ac+2b^{2} -2bc$

$2c^{2} -2a^{2} +2b^{2}$

Taking the common difference 2 and dividing this equation we get

$c^{2} -a^{2} +b^{2}$

By multiplying the whole equation by -1 we get

$a^{2} -b^{2} -c^{2}$