If 2 * 3=√(13) and 3 * 4=5, then the value of 5 * 12 is

ABC26GN1417 · Square Roots and Cube Roots

Subject: General Aptitude · Chapter: Square Roots and Cube Roots · Exam: · Marks: · Difficulty:

If $2 * 3=\sqrt{13}$ and $3 * 4=5$, then the value of 5 * 12 is

(a)$\sqrt{17}$

(b)$\sqrt{29}$

(c)12

(d)13

Answer

Answer (as printed): D

Explanation

Clearly, $a * b=\sqrt{a^{2}+b^{2}} . \quad \therefore 5 * 12$ $$=\sqrt{5^{2}+12^{2}}=\sqrt{25+144}=\sqrt{169}=13 .$$

Explanation as extracted from the printed page; notation may be imperfect.