How can I from the following inequality

(cosq1cosq1) + (cosq2cosq2) +(cosq3cosq3) - 2 cosq1 cosq2 cosq3-1 ≤ 0

Drive the following inequality

cosq1 cosq2 – sqrt[(sinq1sinq1)(sinq2sinq2)]≤ cosq3 ≤ cosq1 cosq2 +sqrt[(sinq1sinq1)(sinq2sinq2)]

sqrt == square root

**Please help**