Question

. If |Ā+B | = |Ā|+|B | then angle between A and B will be (a) 90° (c) 0° (b) 120° (d) 60°
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Answer 1

Answer:

60 angle between. A+B=A+B

Answer 2

Answer:

90 degrees

|A+B|= √A²+B²+2AB cos teata

so,

√A²+B²+2AB cos teata=|A|+|B|

square root on both side

A²+B²+2AB cos teata= A²+B²

A²,B²: cancel on both sides

2AB cos teata= 0

cos teata= 0

teata=90 degree