निम्नलिखित रेखा युग्मों के बीच का कोण ज्ञात कीजिये|
(i) `(x-1)/2 = (y-2)/3 = (z-4)/6, x+1 = (y+2)/2 = (z-4)/2`
(ii) `(x+1)/3 = (y-1)/5 =(z+3)/4, (x+1)/1 = (y-4)/4 =(z-5)/2`
(i) `(x-1)/2 = (y-2)/3 = (z-4)/6, x+1 = (y+2)/2 = (z-4)/2`
(ii) `(x+1)/3 = (y-1)/5 =(z+3)/4, (x+1)/1 = (y-4)/4 =(z-5)/2`
(i) `cos^(-1)20/21`, (ii) `cos^(-1) (8sqrt(3))/15`