Question

(-3x+2y+z) ² class 9
formula hai iska
a²+b²+c²+2ab+2bc+2ca​

Answer 1

$\large\underline{\sf{Solution}}$

Given,=>(-3x+2y+z)²

_____________________

To find=>FACTORISE the expression.

_____________________

Formula used↓

(a+b+c)²=a²+b²+c²+2(ab+BC+ca)

_____________________

We have to FACTORISE the given expression using the identity .

_____________________

$\large\underline{\sf{ {( - 3x + 2y + z)}^{2} }} \\ \updownarrow$

$\small\underline{\sf{ {( - 3x)}^{2} + {(2y)}^{2} + {(z)}^{2} + 2( - 3x \times 2y + 2y \times z + z \times {( - 3)}^{2} }}$

$\small\small{\sf{ {9x}^{2} + {4y}^{2} + {z}^{2} + 2( - 6xy + 2yz - 3xz) }}$

$\small \small \small{\sf{ {9x}^{2} + {4y}^{2} + {z}^{2} + 2 \times - 6xy + 2 \times 2yz + 2 \times - 3xz}}$

$\small \small{\sf{ {9x}^{2} + {4y}^{2} + {z}^{2} - 12xy + 4yz + - 6xz}}$

____________________

$\large\underline{\sf{more \: identities}} \\ \large\underline{\sf{ {(a + b)}^{2} = {a}^{2} + 2ab + {b}^{2} }} \\ \large\underline{\sf{ {(a - b)}^{2} = {a}^{2} - 2ab + {b}^{2} }} \\ \large\underline{\sf{ {a}^{2} - {b}^{2} = (a + b)(a - b)}} \\ \large\underline{\sf{(x +a )(x + b) = {x}^{2} + (a + b)x + ab }}$