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What is (3-x) (3 + x) expansion equal to? (a-b) (a + b) formula? What is (3-x) (3 + x) expansion equal to? The formula of (a-b) (a + b)? What is (3 + x) (3-x) expansion equal to? What is the formula of (a + b) (a-b)? Original formula = (3-x) (3 + x) =3(3-x)+x(3+x) =9-3x+3x+x² =9+x²
9-x^2；
a^2-b^2
The original formula = (3-x) (3 + x) = 3 (3-x) + X (3 + x) = 9-3X + 3x + X & sup2; = 9 + X & sup2; right?
Wrong! The second step of the original formula "3 (3-x) + X (3 + x)" is wrong, should be "3 (3-x) + X (3-x)"
What unit does t represent in mathematics
fast
Tons
What does t mean in mathematics?
8kg=( )t
QSYlala ,
8Kg＝0.008t
T is the ton
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