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सिद्ध कीजिए - `|(sin^2A,sinA,cos^2A),(sin^2B,sinB,cos^2B),(sin^2C,sinC,cos^2C)|=-(sinA-sinB)(sinB-sinC)(sinC-sinA)` |
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Answer» L.H.S.`=|(sin^2A,sinA,cos^2A),(sin^2B,sinB,cos^2B),(sin^2C,sinC,cos^2C)|` `=|(sin^2A,sinA,1-sin^2A),(sin^2B,sinB,1-sin^2B),(sin^2C,sinC,1-sin^2C)|` `=|(sin^2A,sinA,1),(sin^2B,sinB,1),(sin^2C,sinC,1)|` `=|(sin^2A-sin^2C,sinA-sinC,0),(sin^2B-sin^2C,sinB-sinC,0),(sin^2C,sinC,1)|` (संक्रियाओं `R_1toR_1-R_3` और `R_2toR_2-R_3` से ) `=|(sinA+sinC,1,0),(sinB+sinC,1,0),(sin^2C,sinC,1)|` [`R_1` और `R_2` से क्रमशः और `(sinB-sinC)` लेने पर ] `=(sinA-sinC)(sinB-sinC)` `=|(sinA+sinC,,0),(sinB+sinC,,1)|` (`C_3` के अनुदिश प्रसार करने पर ) `=(sinA-sinC)(sinB-sinC)(sinA+sinC-sinB-sinC)` `=-(sinA-sinB)(sinB-sinC)(sinC-sinA)` R.H.S. |
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