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標題:

F.5 more about equations

發問:

1a) rewrite the equation 3sin^2 x+4sinxcosx-4cos^2 x=0 in the form of atan^2 x+btanx+c=0,where a,b and c are integers. b)hence,solve the equation 3sin^2 x+4sinxcosx-4cos^2 x=0, where x is between 0 to 360. pls show clear steps.thx~

最佳解答:

1a) 3sin^2 x+4sinxcosx-4cos^2 x=0 (3sin^2 x+4sinxcosx-4cos^2 x)/(cos^2 x)=0 3tan^2 x+4tanx-4=0 1b) 3sin^2 x+4sinxcosx-4cos^2 x=0 3tan^2 x+4tanx-4=0 (3tanx-2)(tanx+2)=0 tanx=2/3 or -2 x=33.7 or 213.7 or 116.6 or 296.6

其他解答:C8D74AB62542840B