TS EAMCET · Maths · Trigonometric Ratios & Identities
If then
- A
- B
- C
- D
Answer & Solution
Correct Answer
(C)
Step-by-step Solution
Detailed explanation
Given that A+B+C=270° ⇒cos2A+cos2B+cos2C+4sinAsinBsinC =cos2A+2cos2B+2C2cos2B-2C2+4sinAsinBsinC =cos2A+2cos(B+C)cos(B-C)+4sinAsinBsinc =cos2A+2cos(270°-A)cos(B-C)+4sinAsinBsinC =cos2A-2sinAcos(B-C)+4sinAsinBsinC =1-2sin2A-2sin270°-B+CcosB-C+4sinAsinBsinC…
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