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If cos(120^0-alpha)=cos(120^0-beta),0 lt...

If `cos(120^0-alpha)=cos(120^0-beta),0 lt alpha,beta lt pi`, then find the relation between `(alpha and betadot)`

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If `sin A =sinB," where " A =120^@-alpha" and "B=120^@-beta," then " A=Bor A=pi,i.e., A+B=pi`
`rArr 120^@-alpha=120^@-beta or 120^@-alpha+120^@-beta=180^@`
`rArr alpha=beta or alpha+beta=60^(@)`
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CENGAGE PUBLICATION-TRIGONOMETRIC FUNCTIONS -SINGLE CORRECT ANSWER TYPE
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