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Question
Evaluate the following using identities:
(1.5x2 − 0.3y2) (1.5x2 + 0.3y2)
Solution
The given expression is (1.5x2 − 0.3y2) (1.5x2 + 0.3y2)
We shall use the identity `(a + b)(a - b) = a^2 - b^2`
Here `a =1.5x^2`
`b = 0.3y^2`
By applying identity we get
`(1.5x^2 xx 1.5x^2) - (1.5x^2 + 0.3y^2) = (1.5x^2)^2 - (0.3y^2)^2`
`= (1.5x^2 xx 1.5x^2) - (0.3y^2 xx 0.3y^2)`
`= 2.25x^2 - 0.09y^4`
Hence the vlue of `(1.5x^2 - 0.3y^2)(1.5x^2 + 0.3y^2) " is " 2.25x^4 - 0.09y^4`
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