350. 1)1/(√8+3)=(√8-3)/((√8-3)(√8+3))=(√8-3)/(8-9)=-(√8-3)
2) 1/(√5+2)=(√5-2)/((√5+2)(√5-2))=(√5-2)/(5-4)=√5-2=-(2-√5)
351. 1/(√8-√7)=(√8+√7)/((√8-√7)(√8+√7))=(√8+√7)/(8-7)=√8+√7=2√2+√7
2. 5+√24=5+2√6, 1/(5-2√6)=(5+2√6)/((5+2√6)(5-2√6))=(5+2√6)/(25-24)=5+2√6