Question

helo !
Do solve this plz ​

Answer 1

given :-

${(2x}^{2}$ - ${5y}^{2)}$ ${(x}^{2}$ + ${3y}^{2)}$

where x = -1 , y = 2

Solution :-

⠀⠀⠀⠀⠀⠀⠀= ${2x}^{4}$ + ${6x}^{2}{y}^{2}$ - ${5y}^{2}{x}^{2}$ - ${15y}^{4}$

⠀⠀⠀⠀⠀⠀= ${2x}^{4}$ + ${x}^{2}{y}^{2}$ - ${15y}^{4}$

L.H.S :-

⠀⠀⠀⠀⠀⠀=${(2x}^{2}$ - ${5y}^{2)}$ ${(x}^{2}$ + ${3y}^{2)}$

⠀⠀⠀⠀⠀= ${[2(-1}^{2)}$ ${-5(2]}^{2)}$ ${[(-1)}^{2}$ + ${3(2]}^{2)}$

⠀⠀⠀⠀⠀⠀= $2(1+12)$ $-$ $20(1+12)$

⠀⠀⠀⠀⠀⠀= $2$ $+24$ $-20$ $-240$

⠀⠀⠀⠀⠀⠀⠀= -234

R.H.S :-

⠀⠀⠀⠀⠀ = ${2x}^{4}$ + ${x}^{2}{y}^{2}$ - ${15y}^{4}$

⠀⠀⠀⠀⠀⠀= ${2(-1)}^{4}$ + ${(-1)}^{2}{(2)}^{2}$ - ${15(2)}^{4}$

⠀⠀⠀⠀⠀⠀= $2$ $+4$ $-240$

⠀⠀⠀⠀⠀⠀= - 234

${\boxed{\large{\bold{R.H.S\:=\:L.H.S}}}}$