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Help!

which sum is rational?

A.)

\pi + 18
B.)

√(25 + 1.75)
C.

√(3 + 5.5)
D.)

\pi + √(2)

1 Answer

5 votes


\pi+18-irrational\ because\ \pi\ is\ irrational\\\\√(25+1.75)=√(26.75)=\sqrt{(2675)/(100)}=(√(2675))/(√(100))=(√(25\cdot107))/(10)\\\\=(√(25)\cdot√(107))/(10)=(5√(107))/(10)=(√(107))/(2)-irrational\\\\√(3+5.5)=√(8.5)=\sqrt{(85)/(10)}=\sqrt{(850)/(100)}=(√(850))/(√(100))=(√(25\cdot34))/(10)\\\\=(√(25)\cdot√(34))/(10)=(5√(34))/(10)=(√(34))/(2)-irrational


\pi+\sqrt2-irrational

User Santanu C
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