Mohon bantuannya ya teman-teman

No. 15

7(1+√2)(1-√2) / 3+√2
= 7(1-2) / 3+√2
= -7(3-√2) / (3+√2)(3-√2)
= -7(3-√2) / (9-2)
= -7(3-√2) / 7
= -3+√2
>>>B

No. 16

[ x+1/y ] . ³log5
= [ ²log3 + 1/³log2 ] . ³log5
= [ ²log3 + ²log3 ] . ³log5
= 2 . ²log3 . ³log5
= 2 . ²log5
>>>D