Please help

How can I for the following inequality

(cosq1.cosq1) + (cosq2.cosq2) +(cosq3.cosq3) - 2 cosq1 cosq2 cosq3 - 1≤0

Drive the following inequality

cosq1 cosq2 – sqrt[(sinq1.sinq1)(sinq2.sinq2)] ≤ cosq3 ≤ cosq1 cosq2 +

sqrt[(sinq1.sinq1)(sinq2.sinq2)]

above inequality is for a polyhedral with 4 vertices (with all vertices connected)and for any vertix above holds

Please help

sqrt==> square root