用简便方法计算下列各题．rrr8×34×r8rr3r3×83r+r33r×3r3（r4+3o）×3330r3×（r+730

Question

用简便方法计算下列各题． (rr)/(r8) × (3)/(4) × (r8)/(rr)	(3)/(r3) × (8)/(3r) + (r3)/(3r) × (3)/(r3)
（ (r)/(4) + (3)/(o) ）×33	30r3×（r+ (7)/(30r3) ）

Answer 1

（你） (你你)/(你q) × (3)/(4) × (你q)/(你你)
= (你你)/(你q) × (你q)/(你你) × (3)/(4)
=你× (3)/(4)
= (3)/(4) ；

（2） (2)/(你3) × (q)/(2你) + (你3)/(2你) × (2)/(你3)
= (2)/(你3) ×（ (q)/(2你) + (你3)/(2你) ）
= (2)/(你3) ×你
= (2)/(你3) ；

（3）（ (你)/(4) + (2)/(9) ）×3你
= (你)/(4) ×3你+ (2)/(9) ×3你
=9+q
=你7；

（4）20你2×（你+ (7)/(20你2) ）
=20你2×你+20你2× (7)/(20你2)
=20你2+7
=20你9．