In triangle ABC, `R (b + c) = a sqrt(bc)`, where R is the circumradius of the triangle. Then the triangle is
A. isosceles but not right
B. right but not isosceles
C. right isosceles
D. equilateral
Correct Answer - C
`R(b +c) = a sqrt(bc) = 2R sin A sqrt(bc)`
`:. sin A = (b +c)/(2sqrt(bc))`
Now `sin A le 1`
`rArr (b + c)/(2sqrt(bc)) le 1`
or `(sqrtb - sqrtc)^(2) le 0`
or `b = c`
`rArr sin A = 1`
`rArr A = 90^(@) and b = c`
Hence, the triangle is right isosceles.
Area of qudrilateral AbCD is maximum when area of ACD is maximum. Area of triangle ACD.
`Delta_1=(1)/(2)||{:(3/sqrt2,,sqrt2,,),(3/sqrt2,,-sqrt2,,),(3sintheta,,2costheta,,),(3/sqrt2,,sqrt2,,):}||`
`=|-3sqrt(2)costheta+3sqrt(2)sintheta|`
`therefore Delta_1("max")=6`, when`theta=(7pi)/(4)` (as `theta epsilon(3pi//2,2pi`))
Maximum area is 12 sq.units (as...
Correct Answer - A
Since `DeltaABC` is right angled at C, circum-radius, `R = (c)/(2)`
Now, `r = (s -c) tan (C//2) = (s-c) tan (pi//4) = s -c`
Thus, `2(r...
Correct Answer - B
Circumradius of triangle ABC, R = 5
`:.` Circumradius of pedal triangle, `R_(1) = 5//2` and so on.
Now, `underset(i=1)overset(oo)sum R_(i) + R_(1) + R_(2) + R_(3)...