Question

(-2x + 5y - 3z)? expand using identity
​

Answer 1

Answer:

the above answer is correct

Answer 2

$\huge{\underline{\mathfrak{\pink{Question }}}}$

Expand ( -2x + 5y – 3z)^2 using suitable identity

$\huge{\underline{\mathfrak{\pink{Answer}}}}$

( -2x + 5y - 3z)² is of the form (a + b + c)²

( a + b + c)² = a² + b² + c² + 2ab + 2bc + 2ca

where,

-› a = -2x

-› b = 5y

-› c = -3z

∴ (−2x+5y−3z) ² =(−2x) ² +(5y) ² +(−3z)² + 2(−2x)(5y)+2(5y)(−3z)+2(−3z)(−2x)

$= 4 {x}^{2} +25y {}^{2} + 9 {z}^{2} - 20xy - 30xy + 12zx$