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Question
If `veca` and `vecb` are two non-zero vectors such that `|veca xx vecb| = veca.vecb`, find the angle between `veca` and `vecb`.
Solution
Given: `|veca xx vecb| = veca.vecb`
`\implies |veca||vecb| sin θ = |veca||vecb| cos θ`
`\implies` sin θ = cos θ
`\implies` tan θ = 1
θ = 45°
Hence, angle is 45°.
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