问题
解答题
把下列各式在实数范围内分解因式: (1)a2-7;(2)x3-2x;(3)a2-2
|
答案
(1)a2-7=(a+
)(a-7
);7
(2)x3-2x,
=x(x2-2),
=x(x+
)(x-2
);2
(3)a2-2
a+3=(a-3
)2;3
(4)x4-25,
=(x2+5)(x2-5),
=(x2+5)(x+
)(x-5
).5
把下列各式在实数范围内分解因式: (1)a2-7;(2)x3-2x;(3)a2-2
|
(1)a2-7=(a+
)(a-7
);7
(2)x3-2x,
=x(x2-2),
=x(x+
)(x-2
);2
(3)a2-2
a+3=(a-3
)2;3
(4)x4-25,
=(x2+5)(x2-5),
=(x2+5)(x+
)(x-5
).5