Pentru a=50,calculați:a*(a+2)-a*(a-2) urgent dau coroana

a = 50
a × ( a + 2 ) - a × ( a - 2 ) =
= 50 × 52 - 50 × 48 =
= 50 × ( 52 - 48 ) =
= 50 × 4 = 200
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sau: a × ( a + 2 ) - a × ( a - 2 ) = a × ( a + 2 - a + 2 ) = 50 × 4 = 200