tolong bntu ngerjain soal no 4 yg a

4) a. √11+2√24 = √11+2×2√6 = 11+4√6.
b) √17-2√60= √17-2×2√15 = √17-4√15.
c) √21+√320= √21+√8²×5= √21+8√5.
d) √7-√49= √7-7 = √0 =0