Trigonometryno. of solutions of the equation tan^2x-sec^10x+1=0 in (0,10) ? manvi makkar 11 Years agoGrade
Y RAJYALAKSHMI11 Years agotan2x – sec10x + 1 = 0=> sec2x – sec10x = 0 (as 1+ tan2x = sec2x)=>sec2x(1 – sec8x) = 0=>sec2x(1 – secx)(1 + secx)(1 + sec2x)(1 + sec4x) = 0=> sec2x = 0, (1 – secx)= 0 , (1 + secx) = 0, (1 + sec2x)= 0, (1 + sec4x) = 0The real roots are only for sec2x = 0, (1 – secx)= 0 , (1 + secx) = 0sec2x = 0 => secx = 0(1 – secx)= 0 => secx = 1(1 + secx) = 0 => secx = – 1only one solution secx = 1 is in the interval (0, 10) Ans = 1