if sinA+cosA=1 then prove that cosA-sinA=+-1
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Step-by-step explanation:
sinA+CosA=1(given)--1
Sq both sides
(sinA+cosA)^2=
sin^2A+cos^2+2sinAcosA=1
1+2sinAcosA=1
2sinAcosA=0
sinAcosA=0
sinA=0
Now substituting sinA's value
0+cosA=1
cosA=1
Case 1
sinA=0
cosA=1
Let an equation sinA-cosA
0-1=-1
sinA-cosA=-1
Now taking the same equation
sinAcosA=0
cosA=0 and thus by substituting in 1 we get sinA=1
Case 2
sinA=1
cosA=0
Let us take equation sinA-cosA
1-0=1
sinA-cosA=1
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