Question

Perform the indicated operation.
(3a^2 - 7xy)(3a^2 + 7xy)

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Answer 1

`\quad \huge \quad \quad \boxed{ \tt \:Answer }`

`\qquad \tt \rightarrow \: (3 {a}^(2) - 7xy)(3 {a}^(2) + 7xy) = 9 {a}^( 4 ) - 49 {x}^(2) {y}^(2)`

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`\large \tt Solution \: :`

`\qquad \tt \rightarrow \: (3 {a}^(2) - 7xy)(3 {a}^(2) + 7xy)`

`\qquad \tt \rightarrow \:(3 {a}^(2) \sdot3 {a}^(2) ) + (3a {}^(2) \sdot7xy) - (7xy \sdot3 {a}^(2) ) - (7xy \sdot7xy)`

`\qquad \tt \rightarrow \:9 {a}^(4) + 21a {}^(2) xy- 21 {a}^(2) xy - 49 {x}^(2) {y}^(2)`

`\qquad \tt \rightarrow \: 9 {a}^( 4 ) - 49 {x}^(2) {y}^(2)`

or

Apply property :

`\qquad \tt \rightarrow \: (p + q)(p - q) = {p}^(2) - {q}^(2)`

Answered by : ❝ AǫᴜᴀWɪᴢ ❞