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From the top of a building of height 150m, the angles of depression of two cars on either sides of the building are 45° and 60°. Then the distance b/w the cars are
AD is a building
And B & C are two cars
In ABD
tan45=AD/BD
BD=AD/1=150m
And
In ADC
tan60=AD/DC
CD=AD/√3=150/√3 m
BC=BD+DC=150(1+1/√3)
If x – y = 9, then what is the value of (x-25)^3-(y-16)^3?
Given x-y=9
(x-25-y+16)[(x-25)^2+(y-16)^2+(x-25)(y-16)] = (9-9)[(x-25)^2+(y-16)^2+(x-25)(y-16)] = 0
(x-25)^3-(y-16)^3=0
If x-y-√45=1 & x+y=3√5+1 then what is the value of 12xy(x^2-y^2 )?
ATQ
x-y=√45-1
x-y=3√5-1 (i)
x+y=3√5+1 (ii)
multiply (i)&(ii)
we get x^2-y^2=(3√5)^2-1=44 (iii)
adding (i)&(ii)2x=6√5
x=3√5
subtracting (i)&(ii)
y=1
12xy(x^2-y^2 )=12×3√5×1×44=1584√5
O and C are respectively the orthocenter and circumcenter of an acute angled triangle PQR. The points P and O are joined and produced to meet the side QR at S. If ∠PQR = 70° and ∠QCR = 140°, then ∠RPS = ?
∠QPR=1/2 ∠QCR=1/2 x 140=70
And ∠PSQ=90
In PQS
∠QPS=90-70=20
∠RPS=∠QPR-∠QPS =70-20=50
In a ∆PQR, PM is the angle bisector of ∠QPR and ∠QPM=60°. What is the length of PM?
Chords AC and BD of a circle with centre O intersect at right angles E. If ∠OAB = 35°, then the value of ∠EBC is :
Join OB and OA
Now in OAB
OA=OB=radius
∠OBA=∠OAB=35
∠AOB=180 – (∠OBA+∠OAB) =180 – (35+35) =110
Now angle made by same chord at the center & circumference
∠ADB= ½ x 110=55=∠ADE=∠BCE
∠EBC=180-(90+55)=35
The base of a right prism is an equilateral triangle if the lateral surface area and volume is 100 respectively, then the length of the side of base of the prism is
Lateral surface area = base permeter x h
150 = 3 x side x h
Side x h = 50 sq m (i)
Volume of prism = area of base x height
100√3=√3/4×side^2×h
H x side^2=400 cucm(ii)
Dividing eq (ii) by (i)
Side= 400/50=8cm
Find the value of (sinA+sinB)/(cosA+cosB)
We know that
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