Question

find the following products
$(3a {}^{4} + 5)(9a {}^{8} - 15a {}^{4} + 25)$
please fast ⏩
And give full answer I humbly request to you
ANSWER =
$27a {}^{12} + 125$
​

Answer 1

$\text{we \: know \: that : } \\ \\ \hookrightarrow \green{\boxed{\sf \: \: \rm{ \pink {{x}^{3} + {y}^{3} = (x + y)( {x}^{2} - xy + {y}^{2} )}}}} \\ \\ \bf \to \: given : \\ \\ \orange{ \boxed{ \begin{array}{cc} \rm \: (3 {a}^{4} + 5)(9 {a}^{8} - 15 {a}^{4} + 25) \\ \\ \rm = (3 {a}^{4} + 5) \{(3 {a}^{4}) {}^{2} - 3 {a}^{4} .5 + {5}^{2} \} \\ \\ \sf \: let \: concider \: : \\ \rm \: \pink{x} = 3 {a}^{4} \: \: \: and \: \: \pink{ y }= 5 \\ \\ \rm = ( \underbrace{3 {a}^{4} }_{\pink{x}} + \underbrace{5}_{\pink{y}}) \{ \underbrace{{(3 {a}^{4} })^{2} }_{\pink{ {x}^{2}}} - \underbrace{3 {a}^{4} }_{\pink{x}}.\underbrace{5}_{\pink{y}} + \underbrace{ {5}^{2} }_{ \pink{{y}^{2}} }\}\\ \\ \sf \: apply \: the \: upper \: formula \: \\ \\ = {(3 {a}^{4} })^{3} + {5}^{3} \\ \\ = 27 {a}^{12} + 125 \\ \\ = \sf \: answer \end{array}}}$

Answer 2

Answer:

Step-by-step explanation: