Question

find the angle between the lines whose direction ratios are 5 ,- 12,13 and -3,4,5 ​

Answer 1

Answer:

cos theta=| a 1 a 2 +b 1 b 2 +c 1 c 2 sqrt a 1 ^ 2 +b 1 ^ 2 +c 1 ^ 2 sqrt a 2 ^ 2 +b 2 ^ 2 +

=| 15-48-65 sqrt 25+144+169 sqrt 9+16

=|- 98 13 sqrt 2 *5 sqrt 2 |

=|- 98 13*5*2 |

= 49 65

theta = arccos(49/65)