In a right - angled triangle PQR, ∠Q is right angled, and S is a point on the side PQ. Find the value of PS.
In a right - angled triangle PQR, ∠Q is right angled, and S is a point on the side PQ. Find the value of PS. Correct Answer √{RS<sup>2</sup> – PR<sup>2</sup> + (2 × PQ × PS)}
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In ΔPQR:
PR2 = PQ2 + QR2
QR2 = PR2 – PQ2 ----(1)
In ΔSQR:
RS2 = QS2 + QR2
QR2 = RS2 – QS2 ----(2)
From (1) and (2):
PR2 – PQ2 = RS2 – QS2
QS2 = RS2 + PQ2 – PR2
(PQ – PS)2 = RS2 + PQ2 – PR2
PQ2 + PS2 – (2 × PQ × PS) = RS2 + PQ2 – PR2
PS2 = RS2 – PR2 + (2 × PQ × PS)
PS = √{RS2 – PR2 + (2 × PQ × PS)}
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Feb 20, 2025