3) In APQR, PQ = 9 cm, PR = 18 cm and QR = 943 cm. Find the measure of
angle P.
Answers
Answered by
3
→Answer :
R.E.F. Image.
Given ΔPQR is right angle triangle with QR=9cm
& PR−PQ=1cm
then PR=(1+PQ)
squaring both sides
(PR)
2
=(1+PQ)
2
=1+(PQ)
2
+2PQ
(PR)
2
−(PQ)
2
=1+2PQ
(QR)
2
=1+2PQ [PR
2
=PQ
2
+QR
2
]
81−1=2PQ
[PQ=40cm]
now, using Pythagoras theorem. or equation (1) we have
PR−PQ=1
[PR=41cm]
now sinR=
PR
PQ
=
41
40
cosR=
41
9
=
PR
QR
then sinR+cosR=
41
40
+
41
9
=
41
49
.
sinR+cosR=
41
49
.
Answered by
0
Given ΔPQR is right angle triangle with QR=9cm
& PR−PQ=1cm
then PR=(1+PQ)
squaring both sides
(PR)
2
=(1+PQ)
2
=1+(PQ)
2
+2PQ
(PR)
2
−(PQ)
2
=1+2PQ
(QR)
2
=1+2PQ [PR
2
=PQ
2
+QR
2
]
81−1=2PQ
[PQ=40cm]
now, using Pythagoras theorem. or equation (1) we have
PR−PQ=1
[PR=41cm]
now sinR=
PR
PQ
=
41
40
cosR=
41
9
=
PR
QR
then sinR+cosR=
41
40
+
41
9
=
41
49
.
sinR+cosR=
41
49
.
solution
Similar questions