Question

how the following trace elements can be controlled?
lead
copper
cadmium
zinc
Tin
cobalt
mercury
selenium
chromium
arsenic​

Answer 1

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☃ ƛƝƧƜЄƦ ☃

Hey !!

$LHS = ( 1 + 1/tan² A ) + ( 1 + 1/Cot²A )$

$= ( 1 + Cot²A ) ( 1 + Tan²A )$

$=> Cosec²A × Sec²A$

$=> 1/Sin²A × 1/Cos²A$

$=> 1/Sin²A Cos²A$

$=> 1/Sin²A ( 1 - Sin²A )$

$=> 1/ Sin²A - Sin⁴A ) = RHS$

$Hence,$

$LHS = RHS = 1/ Sin² A - Sin⁴A .$

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