Question

两个计算题.过程.第一题.√12+2分之根号3第二题.先化简,再求值（a+1分之2+a^-1分之a+2）÷a+1分之a,

Answer 1

√12+√3/2 =2√3+√3/2=5√3/2

[ 2/(a+1)+(a+2)/a^-1] ÷[a/(a+1)]

= [2/(a+1)+ a(a+2)]*(a+1)/a

= [2+a(a+1)(a+2)]/a

= 2/a + (a+1)(a+2)

= 2/(√3+1) + (√3+2)(√3+3)

= (√3-1) + 9 + 5√3

= 8+6√3