Track / Stage 4 / 125 of 340 #385 of 2000

Problem 385

AMC 12 late, AIME early

Geometry Difficulty 4.7 Find the answer

10. Given that the circumcenter of $\square A B C$ is $\mathrm{O}$ , and $2 \overrightarrow{O A}+3 \overrightarrow{O B}+4 \overrightarrow{O C}=0$ , then the value of $\cos \angle B A C$ is $\qquad$

Your answer

Official solution

10、 $\frac{1}{4}$

Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic, difficulty and ordering added by this site.