7.5^2*2.4-2.5^2*2.4 29.8^2-0.2^2 (1)7.5^2*2.4-2.5^2*2.4 (2) 29.8^2-0.2^2

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7.5^2*2.4-2.5^2*2.4 29.8^2-0.2^2 (1)7.5^2*2.4-2.5^2*2.4 (2) 29.8^2-0.2^2
7.5^2*2.4-2.5^2*2.4 29.8^2-0.2^2
(1)7.5^2*2.4-2.5^2*2.4
(2) 29.8^2-0.2^2

7.5^2*2.4-2.5^2*2.4 29.8^2-0.2^2 (1)7.5^2*2.4-2.5^2*2.4 (2) 29.8^2-0.2^2
7.5^2*2.4-2.5^2*2.4
=(7.5²-2.5²)×2.4
=(7.5+2.5)×(7.5-2.5)×2.4
=10×5×2.4
=5×24
=120
29.8^2-0.2^2
=(29.8+0.2)×(29.8-0.2)
=30×29.6
=3×296
=3×(300-4)
=900-12
=888