yuni

the position vectors of the point A,B & C respect to O are a=3i-2j+4k, b=i+3j-4k, c=-2i+5j-3k. Find a)the angle between a+b and a-b b)lamdar if vector a is perpendicular to b+lamdar k.

Find the interior angle formed by points A(1,5,3) , B(-2,3,7) , C(3,2,5). does this mean i need to find all the 3 angles of triangle?

KMn04 with iron(II) ammonium sulphate hexahydrate-redox titration. 1-what is the purpose of adding H2SO4 to iron sample before the titration? 2-why is there no indicator used to determine the end point for this titration? 3-suggest another possible oxidis...