2012 Fujian Question 2 Single-choice Differentiating 2012_退役省自主命题 (2012·理) 2.等差数列{an}中,$a1+a5=10,a4=7,$则数列{an}的公差为 A. 1B. 2C. 3D. 4 Answer keyB ☆ SaveCan't do it, show the explanation查看原卷 →