Justify whether True or false. Solve and please do not send any links for the query . Thnx for your help.
Q. cos θ = a 2 + b 2 2 a b where a and b are two distinct numbers such that ab > 0.

Dear student
For simplicity taking θ=A

cosA=a2+b2-2ab+2ab2ab=a-b2+2ab2ab=a-b22ab+2ab2ab=a-b22ab+1Since, a-b2>0 and ab>0So, cosA=a-b22ab+1>1, which is not possible as maximum value of cosA is 1.Hence, it is false.

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